PubMed HealthSearch

Biomedical subjects

S Ruggieri

Publications and source records attributed to S Ruggieri.

At least 91 records · Page 5Linked to original sources

Ganglioside composition of substrate-adhesion sites of normal and virally-transformed Balb/c 3T3 cells.

The ganglioside composition of the so-called substrate-attached material (SAM), which remains tightly bound to the tissue culture dish after cells are detached by chelating agents, was compared with the ganglioside composition of released cell bodies in the cultures of normal and various virally-transformed Balb/c 3T3 cells. Regardless of whether the cells were untransformed or transformed, the SAM of their cultures shows a ganglioside structure characterized by a prevalence of the higher homologs, mainly GD1a, over the simpler gangliosides, even when the level of higher homologs was reduced in the cell bodies of transformed cells. This result cannot be ascribed to the presence of plasmamembranes in the SAM as shown by ganglioside analysis of the plasmamembranes of some of the cells under study. Only in a highly metastatic transformed cell line did the SAM contain the same low GD1a level as found in the cell bodies.

Animals

Roles of gangliosides in the surface properties of normal and malignant cells.

Gangliosides are ubiquitous plasma membrane components whose structural characteristics make it possible to establish multiple interactions with the pericellular microenvironment. Several receptorial activities of gangliosides have already been recognized and the possible involvement of gangliosides in growth control, adhesion, differentiation, and immunologic recognition is at present under study. The study of the role of gangliosides in cell growth control has been approached in our laboratory by investigating whether the ganglioside changes found in SV40-transformed Balb/c3T3 cells (SV3T3 cells) revert to a normal pattern in a variant of SV3T3 cells with growth properties similar to those of normal parental cells, the concanavalin A-selected SV3T3 revertant cells. These latter cells showed the same reduction of the more complex gangliosides as found in SV3T3 cells, while their amount of II3NeuAC-LacCer (GM3) was greatly increased compared to that found in either normal or transformed 3T3 cells. In order to study the role of gangliosides in the adhesion process, we analyzed the ganglioside structure of the so-called substrate-attached material, a cell surface structure involved in the adhesion of cells to substrate, from cultures of Balb/c3T3, SV3T3, and concanavalin A-selected SV3T3 revertant cells and from cultures of a system of transformed cells with different metastatic potential: the nonmetastatic B77-3T3 and the highly metastatic AA6 cells. Compared to normal cells, all the transformed cells contained smaller quantities of gangliosides in their substrate-attached material.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Thymosin beta arg10, a major variant of thymosin beta 10 in rabbit tissues.

Two homologous peptides, designated thymosin beta 4 and thymosin beta 10, respectively, have been shown to be widely distributed in mammalian cells and tissues (S. Erickson-Viitanen, S. Ruggieri, P. Natalini, and B.L. Horecker (1983) Arch. Biochem. Biophys. 221, 570-576; S. Erickson-Viitanen, S. Ruggieri, P. Natalini, and B.L. Horecker, (1983) Arch. Biochem. Biophys. 225, 407-413). In the rabbit, thymosin beta 4 is replaced by a variant, thymosin beta ala4, that contains alanine in place of serine at the blocked NH2-terminus. It is reported that in rabbit tissues thymosin beta 10 is also replaced by a variant, designated thymosin beta arg10, that contains an additional amino acid, arginine, inserted following lysine-38. The rabbit tissues analyzed also differ from those of other mammals in the relative quantities of thymosin beta ala4 and beta arg10, which are nearly equal, compared to tissues from other mammals where the quantities of thymosin beta 10 are only one-third to one-tenth those of thymosin beta 4.

Amino Acid Sequence

Thymosin beta 10, a new analog of thymosin beta 4 in mammalian tissues.

A new analog of thymosin beta 4 has been isolated from tissues of several mammalian species. This peptide, designated thymosin beta 10, is composed of 42 amino acid residues and shows 75% sequence homology with thymosin beta 4. It occurs together with thymoxin beta 4 in a variety of tissues including spleen, liver, and thymus and also in several cultured cell lines. In the spleen of rat, mouse, cat, and man, the new peptide accounts for approximately 0.02% by weight of the total protein. In the calf it is replaced by another homologous peptide, designated thymosin beta 9, whose structure has been reported.

Amino Acid Sequence

Distribution of thymosin beta 4 in vertebrate classes.

A peptide containing 43 amino acid residues, rich in glutamic acid and lysine, was originally isolated from calf thymus and designated thymosin beta 4 [T.L.K. Low, S. -K. Hu, and A. L. Goldstein (1981) Proc. Nat. Acad. Sci. USA 78, 1162-1166]. However, thymosin beta 4 was also shown to be present in other tissues of rats and mice, with highest concentrations in spleen and peritoneal macrophages [E. Hannappel, G.-J. Xu, J. Morgan, J. Hempstead, and B.L. Horecker (1982), Proc. Nat. Acad. Sci. USA 79, 2172-2175]. We have now identified the same peptide in tissues of other mammalian species and other vertebrate classes, including birds and amphibia. Exceptions are the rabbit and bony fish, where thymosin beta 4 is replaced by different peptides, similar in size and in amino acid sequence. None of these peptides was detected in several invertebrates or in the protozoan, Tetrahymena pyriformis. In subcellular fractionation of rat spleen, thymosin beta 4 was recovered in the cytosol.

Animals

Post-traumatic headache: neuropsychological and clinical aspects.

Seventy patients suffering from post-traumatic headache were studied. Pain characteristics, personality and intellectual functions were assessed to be related to cranial trauma. No evident signs of brain damage were present, but an impairment related to pain in personal adjustment and well-being reducing work and study capabilities was identified. A psychopathological condition described as anxiety with somatizations and conversion mechanisms was found and when compared with the psychopathological characteristics from a group of common headache patients no differences were obtained between the two groups. DSM III diagnostic possibilities for post-traumatic headache patients were discussed.

Adult

Abnormal involuntary movements: a study of dopaminergic receptor interaction.

UNLABELLED: Abnormal involuntary movements caused by chronic levodopa treatment in Parkinson's disease, tardive dyskinesia resulting from long-term treatment with neuroleptics, and Huntington's disease all seem to be related to functional alteration and/or derangement of the DA/ACh systems. Recent data show the presence of different types of DA receptors D1 and D2, which seem to be involved in the pathogenesis of AIM: an alteration of their mutual equilibrium could account for movements disorders. In addition, hypofunction of the ACh system also seems to play a role in the pathogenesis of AIM. The purpose of this study was to verify an alteration of DA/ACh relationships by evaluating the clinical responses to pharmacological stimuli in patients affected by AIM secondary to chronic levodopa and chronic neuroleptic treatment. The following drugs were used to evaluate the DA receptors: lisuride (0.007 mg/kg i.v.) and tiapride (2.85 mg/kg i.v.) as agonist and antagonist, respectively, at D2 receptors; oxopentphylline (2.85 mg/kg i.v.) and alpha-flupenthixol (.057 mg/kg p.o.) as agonist and antagonist, respectively, at D1 receptors. Levodopa plus carbidopa (250 mg + 25 mg) was also used. The ACh system was studied using orphenadrine (1.1 mg/kg i.v.) as an antagonist and physostigmine (0.014 mg/kg i.v.) and neostigmine (0.26 mg/kg i.v.) as agonists. Our results suggest an involvement mainly of D1 receptors in the pathogenesis of TD, whereas D2 receptors seem to be important in the onset of AIM after chronic levodopa treatment in Parkinson's disease.

Aged

Ether-linked lipids of Balb/c3T3, SV3T3 and concanavalin A-selected SV3T3 revertant cells.

Ether-linked lipids were analyzed in Balb/c3T3, SV3T3 and Concanavalin A-selected SV3T3 revertant cells. The three cell lines were found to contain significant quantities of alk-1-enyl- and alkyl-linked phosphatidylethanolamine (PE) and phosphatidylcholine (PC) and small amounts of alkyldiacylglycerols. Compared to 3T3 cells, SV3T3 cells contain a higher amount of alk-1-enyl-linked PC, while in SV3T3 revertant cells the concentrations of the various ether lipids are similar to those of 3T3 cells. The major difference in the composition of ether groups of SV3T3 cells, compared to 3T3 cells, is an increase of 18:0 accompanied by a decrease of 18:1 in the alk-1-enyl-linked PE and PC. Alk-1-enyl-linked PC of SV3T3 revertant cells also shows an increase of 18:0, while the decrease of 18:1 was not statistically significant.

Alcohols

Prolactin response to acute administration of different L-dopa plus decarboxylase inhibitors in Parkinson's disease.

Plasma prolactin (PRL) levels modifications after acute administration of L-dopa, L-dopa plus carbidopa and L-dopa plus benserazide were studied in parkinsonian patients. PRL increase after benserazide was compared with PRL response after carbidopa at the same dosage in untreated parkinsonian patients. A further study of the hyperprolactinemic effect of benserazide was performed in vitro on isolated and dispersed rat pituitary cells. The data gathered indicate that benserazide-induced hyperprolactinemia in parkinsonian patients could be due to a direct effect of the drug at the hypothalamic level and consequently to an inhibition of dopamine decarboxylation in the tuberoinfundibular dopaminergic system. It is not possible to exclude, however, that benserazide could exert its biological activity through the production of active metabolites in vivo.

Aged

New strategies in the management of Parkinson's disease: a biological approach using a phospholipid precursor (CDP-choline).

CDP-choline, an intermediate in the phospholipid metabolic pathway supposed to improve the functionality of the dopamine (DA) system, was administered to parkinsonian patients in a double-blind cross-over study versus placebo. All patients were already treated with L-dopa + dopa decarboxylase inhibitor. Clinical evaluations were carried out using the Webster Rating Scale (WRS), the Northwestern University Disability Scale (NUDS) and a semiquantitative rating scale for tremor, rigidity and bradykinesia. CDP-choline treatment showed a significant improvement of rigidity and bradykinesia and a less important amelioration of tremor. NUDS and WRS showed a similar positive result. Comparing the results obtained by placebo, we found that the actual clinical efficacy of CDP-choline regards mainly bradykinesia and rigidity (23 and 33% improvement, respectively). The positive effect of CDP-choline on parkinsonian patients already treated with L-dopa + dopa decarboxylase inhibitor stands for a possible action on the DA receptor through an activation of the phospholipid metabolism.

Adult

Isolation of yeast nuclei. Evidence of chromatin-associated proteolytic activity.

Purified yeast nuclei contain proteolytic activities which are associated with chromatin. pH optimum is in the range 8.0--8.5. Partial purification reveals the presence of three fractions corresponding to different molecular weights. Boiled chromatin supernatants are able to inhibit proteolytic activity. The inhibition effect of various compounds is also described. The purity of the chromatin preparation seems to rule out artifacts due to contamination.

Cell Fractionation

Definition and therapy of chronic cerebro-vascular diseases.

Chronic cerebro-vascular disorders could be considered in a broad sense as a large body of knowledge in which three main categories of clinical disturbances have to be be considered: 1) Pathological aging that manifest itself with light short term memory impairment associated with a mild parkinsonian symptomatology or pseudobulbar signs. 2) Senile dementia Alzheimer type and multi infarct dementia. 3) Chronic cerebro-vascular disorders as defined by the Ad Hoc Committee (Paris, 1980). At present the therapy of chronic cerebro-vascular disorders is based on two main groups of drugs and can be divided into: 1) A treatment of prevention or secondary prevention which tends to correct or modify the different risk factors. 2) A treatment that seeks to control and modify the neurological and neuropsychological after effects and the disorders of the higher nervous activities which result from the lesion.

Cerebrovascular Disorders

Neutral glycolipids and gangliosides of concanavalin A-selected SV3T3 revertant cells and of normal and SV40-transformed Balb/c 3T3 cells.

The structural analysis of neutral glycolipids and gangliosides of the SV40 transformed Balb/c3T3 cells (SV3T3 cells) and concanavalin A-selected SV3T3 revertant cells, both compared with untransformed Balb/c3T3 cells, has shown: (i) a content of neutral glycolipids in revertant cells near to that found in the untransformed parental cells; (ii) a similar decrease of the higher gangliosides in transformed and revertant cells; (iii) a content of ganglioside GM3 in revertant cells much higher than that found in both SV3T3 and untransformed Balb/3T3 cells. The possible role of ganglioside GM3 in growth control is discussed.

Animals

Prolactin response as an index of dopaminergic receptor function in Parkinson's disease. Correlation with clinical findings and therapeutic response.

Circadian rhythms of prolactin have been evaluated in thirteen untreated parkinsonian patients before and after 15 days of treatment with L-Dopa + carbidopa. The 24th secretory pattern was not significatively different from that observed in controls. The L-Dopa + carbidopa therapy does not change the basal circadian prolactin (PRL) rhythm. These results suggest that the tubero-infundibular dopaminergic system (TIDA) and the PRL secretion are conserved in untreated parkinsonian patients (PP). During chronic L-Dopa + carbidopa therapy, the basal PRL levels, evaluated in 21 PP, showed a correlation with the severity of clinical features. The effects of single doses of apomorphine, bromocriptine, lisuride and haloperidol, were studied on serum levels of PRL in 21 PP divided in two groups of "responders" and "non-responders". Haloperidol induced an enhancement of serum PRL; the dopaminergic drugs, apomorphine, bromocriptine and lisuride inhibited basal PRL secretion. It seems that the TIDA system, in Parkinson disease is not significatively altered, even though presenting a remarkable slower response in "non-responders" to L-Dopa therapy. We also evaluated the effect of L-Dopa, L-Dopa + carbidopa, bromocriptine, lisuride, nomifensine and deprenyl on growth hormone secretion in six PP. The endocrine effects of dopaminergic drugs show a mild rise in comparison with controls suggesting an important alteration in the dopamine (DA) control of growth hormone (GH).

Adult

Lipid composition of Balb/c3T3, SV3T3, and Concanavalin A-selected revertant cells grown in media containing lipid-depleted serum.

The effects of growth in media supplemented with lipid-depleted fetal calf serum (LDS-media) on morphology, saturation density, and lipid composition were studied in Balb/c3T3, SV3T3, and Concanavalin A selected SV3T3 revertant cells (SV3T3 Rev cells). Cells grown in media containing complete fetal calf serum (FCS-medium) or reconstituted FCS (RS-medium) were used as controls. Growth in LDS-media reduced saturation densities of both SV3T3 and SV3T3 Rev cells while it affected only slightly the saturation density of normal parental cells. Similar inhibitory effects on growth were also induced by exposure of RS-medium. Growth in LDS-medium did not change the typical morphology of the three cell lines. 3T3, SV3T3, and SV3T3 Rev cells grown in LDS-medium showed an accumulation of triacylglycerols and free fatty acids together with a reduction of free cholesterol. All these changes were also present, however, in cells grown in these changes were also present, however, in cells grown in RS-Medium. Growth in LDS-medium induced an increase of 16:1 and 18:1, a decrease of 20:4, and an accumulation of 20:3 (n-9) in phosphatidylethanolamine, phosphatidylcholine, and phosphatidylinositol + phosphatidylserine of 3T3 cells. By contrast, only a slight accumulation of 20:3 (n-9) accompanied by a moderate increase of monoenoic acids was found in the phospholipids of SV3T3 cells grown in LDS-medium. SV3T3 Rev cells grown in LDS-medium showed changes in phospholipid fatty acids composition similar to those found in SV3T3 cells grown under the same conditions.

Animals