Search PubMed⌕ Search

Biomedical subjects

S Ferrari

Publications and source records attributed to S Ferrari.

At least 307 records · Page 17Linked to original sources
PubMed1990

Differential effects of c-myb and c-fes antisense oligodeoxynucleotides on granulocytic differentiation of human myeloid leukemia HL60 cells.

To gain some insight into the role of c-myb and c-fes in myeloid differentiation, the authors have analyzed the ability of HL60 cells to differentiate in response to several different inducers after inhibition of c-myb and c-fes function. This function has been inhibited almost completely by using deoxynucleotides complementary to two 18-nucleotide sequences of c-myb and c-fes encoding mRNA. After 5 days in culture, in several separate experiments with different oligomer preparations, more than 90% growth inhibition was observed in c-myb antisense-treated HL60 cells. At this time, independent of the differentiation inducer used, c-myb antisense-treated HL60 cells differentiate only along the monocytic pathway, whereas in sense oligomer-treated cultures, retinoic acid and dimethyl sulfoxide induced granulocytic differentiation. No perturbation of the HL60 cell growth was observed after 5 days of treatment with antisense c-fes oligomer. However, induction to granulocytic differentiation by retinoic acid and dimethyl sulfoxide resulted in progressive cell death, whereas monocytic differentiation by other differentiation inducers was only marginally affected. These results suggest that granulocytic, unlike monocytic, differentiation requires c-myb-conditioned proliferation and the activity of the protein encoded by c-fes.

Cell Cycle↗
PubMed1990

AIDS--associated predominantly sensory neuropathy. The role of herpes viruses.

Three patients with predominantly sensory neuropathy in course of HIV-1 infection are reported. In all cases ultrastructural examination showed herpes virus-like particles in the axoplasmic matrix of myelinated fibers and in endoneurial macrophages. In 2 cases clinical patterns of posterior column involvement were observed.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Detection of low abundance mRNA of myeloid specific genes in cells of acute and chronic lymphoid leukemias by cRNA hybridization.

The hybridization to a complementary RNA (cRNA) probe both in situ and in solution was used to assay tiny amounts of mRNA of the lactoferrin (LF) and myeloperoxidase (MPO) genes in normal bone marrow cells and in acute and chronic lymphoid leukemias. Evidence is reported that this technique is much more sensitive than the standard Northern blot technique. The LF mRNA was detectable in three of seven cases of acute lymphoblastic leukemia (ALL) and in three of seven cases of chronic lymphocytic leukemia (CLL). Four cases of ALL were also positive when tested with the MPO cRNA. It is apparent from these results that myeloid specific mRNA, different from MPO, may be detected in leukemic cells with lymphoid phenotype using a method more sensitive than the Northern blot technique. Whether or not the molecular events observed in these cell populations reflect events physiologically occurring rather than a deregulation of gene expression associated to leukemogenesis remains to be established.

Bone Marrow↗
PubMed1989

A stimulated S6 kinase from rat liver: identity with the mitogen activated S6 kinase of 3T3 cells.

A number of approaches were tested for their ability to induce S6 phosphorylation and S6 kinase activation in rat liver, including i.p. injection of insulin, sodium orthovanadate or cycloheximide, as well as refeeding starved animals. All treatments led to increased S6 phosphorylation and activation of the apparent same enzyme. The most potent activator of the S6 kinase in liver extracts was cycloheximide. Maximum activation was achieved in 20 min at 1 mg cycloheximide/100 g body weight, with half-maximal activation in 10 min. Based on these findings a large-scale kinase purification procedure was established involving seven steps of chromatography. Following the final step a major protein band of Mr 70,000 was revealed. The protein was purified 20,000-fold, had a sp. act. of 640 nmol/min/mg of protein towards S6, autophosphorylated and was inactivated by phosphatase 2A. Peptide maps of autophosphorylated material were identical to those derived from the mitogen-activated kinase of 3T3 cells.

Animals↗
PubMed1989

Expression and secretion of chicken apolipoprotein AI in transfected COS cells.

A full-length chicken apolipoprotein A-I (apoAI) cDNA has been cloned into an expression vector, pRSVapoAI. This plasmid was transfected into a monkey kidney (COS-1) cell line in order to study apolipoprotein-lipid assembly. Chicken apoAI is the major apolipoprotein of chicken high-density lipoprotein (HDL), which is less complex in apolipoprotein content than the HDL of human plasma. The transient transfected COS-1 cells synthesized and secreted authentic plasma apoAI. Under serum-free medium conditions, COS cells secreted only proapoAI. A small portion (15%) of the secreted apoAI floated at a density 1.07-1.20 g/ml. Upon incubation with fetal bovine serum at 10 degrees C, a majority of the apoAI was recovered in the HDL density (1.06-1.20 g/ml) region. Secreted apoAI was labeled when transfected COS cells were incubated with [U-14C]palmitate, but the incorporation of radioactivity was not the result of fatty acid acylation through ester bond formation. These results indicate that heterologous COS-1 cells are capable of synthesizing and secreting apoAI, and that intracellular association of apoAI with lipids is not necessary for secretion.

Acylation↗
PubMed1989

Effect of fish oil supplementation on erythrocyte lipid pattern, malondialdehyde production and glutathione-peroxidase activity in psoriasis.

Erythrocytes from psoriatic patients have a significant increase in polyunsaturated fatty acids (p less than 0.001) especially in arachidonic acid (p less than 0.001). Glutathione peroxidase activity, in both erythrocytes and platelets, was stimulated when compared with normal cells (p less than 0.001, less than 0.02, respectively) and the production of malondialdehyde was also increased in psoriasis (p less than 0.01). The level of plasma selenium was significantly reduced (52.80 vs 72.49 ng/ml; p less than 0.001). alpha-Tocopherol and retinol were both normal in plasma of psoriatics. After two months of fish oil supplementation, the erythrocyte lipid pattern was changed, eicosapentaenoic and dochesaenoic acids substituting the arachidonate in the membrane. A reduction in malondialdehyde (p less than 0.01), a prolongation of bleeding time (p less than 0.05) and a further stimulation of glutathione-peroxidase (p less than 0.001) in both erythrocytes and platelets was also found.

Adult↗
PubMed1989

Tissue-specific regulation of the concentration of calbindin D28K mRNA in the developing chicken.

A BamHI-HindIII restriction fragment containing the 5'-terminal portion of the gene encoding chicken Calbindin D28K was sequenced and used as a probe in Northern-blot hybridizations to RNA extracted from the brain and intestine of chickens at various stages of development. In both tissues Calbindin D28K mRNA consists of a family of three species, which differ by size. In the intestine Calbindin D28K mRNAs appear at hatching and reach a peak at day 7. In the brain the same RNA species are easily detected at least 7 days before hatching, show a moderate increase at hatching and remain essentially constant during the first 10 days of adult life. The concentration of Calbindin D28K mRNAs in the intestine is strictly dependent on Vitamin D, while it is not in the cerebellum.

Animals↗
PubMed1989

Cytogenetic and molecular studies in primary myelofibrosis.

Cytogenetic and molecular data of three patients affected by primary myelofibrosis with myeloid metaplasia (PMMM) evolving to blastic crisis are reported. The cytogenetic findings were uncommon. The first patient (female) showed an idic(X)(q13) as the sole alteration in chronic phase, with an additional r(7) in 67% of the cells of the blast crisis; the other two patients showed, in blast crisis, a partial trisomy of the long arm of chromosome 1, without translocation, as a unique structural abnormality. These findings confirm the presence of nonrandom, although nonspecific, alterations in PMMM that, in our cases, seem to be related to the multistep progression of the neoplastic process. Molecular investigations have been applied to study the genomic organization and the level of expression of genes such as bcr and calcyclin and c-fms protooncogene possibly involved in the molecular mechanisms underlying cell proliferation in hematopoietic cells. The data obtained are discussed with respect to the myeloproliferative disorder.

Aged↗
PubMed1989

Effects of an olive-oil-rich diet on erythrocyte membrane lipid composition and cation transport systems.

1. In this study we sought to test the possibility that an olive-oil-rich diet might influence the membrane lipid composition and cation transport mechanisms in erythrocytes. 2. To this end, 11 normotensive normolipidaemic healthy volunteers were given a standard relatively low fat diet (28% of total energy) for 3 weeks, followed by a high fat (38% of total energy), olive-oil (100 g/day)-enriched diet for the 3 subsequent weeks, in a metabolic ward. The two diets contained the same amount of cholesterol (400 mg), and the polyunsaturated fatty acid/saturated fatty acid ratio was similar and comparatively low (0.35 on the standard vs 0.36 on the olive oil diet). 3. At the end of the study the lipid composition of the erythrocyte membranes showed the following changes: the oleic acid content increased by 15.7% and the amount of saturated fatty acid decreased by 3.2%. The polyunsaturated fatty acid content tended to decrease, while the polyunsaturated fatty acid/saturated fatty acid ratio did not change significantly. The cholesterol/phospholipid molar ratio increased significantly by 7.8%, still remaining within the reference range. 4. At the same time, the mean values of the maximum rates of the cation fluxes mediated by the Na+ -K+ pump, and by Na+ -K+ co-transport rose significantly, while the maximal rate of Na+ -L+ countertransport showed a non-significant trend towards lower values. 5. Urinary excretion of Na+ and K+, body weight and blood pressure did not change significantly.

Adult↗
PubMed1989

Steroid hormone sulphation in lead workers.

The metabolism of steroid hormones has been investigated in 10 workers exposed to lead and in 10 non-exposed subjects to determine whether lead interferes with the first or second phase reactions of steroid hormone biotransformation, or both. In the exposed workers blood lead concentrations (PbB) ranged from 45 to 69 micrograms/100 ml; in the controls PbB was less than 25 micrograms/100 ml. No statistical differences were found for the total amount of the urinary hormone metabolites, but a drop of about 50% was observed for the sulphated portion. It is suggested that lead interferes with the mechanisms of sulphoconjugation through an effect on the cytosol enzymes sulphotransferase and sulphokinase.

Adult↗
PubMed1989

Plasma lipoproteins, tissue cholesterol overload, and skeletal muscle apolipoprotein A-I synthesis in the developing chick.

In the present study we investigated the changes of plasma lipids, lipoproteins, and tissue lipids that occur during the late embryonic life (5 days before hatching) and the postnatal period (0, 2, 7, 14, and 30 days after hatching) of the chick. The chick emerges from the egg with extreme hypercholesterolemia associated with a high level of cholesterol-rich VLDL + IDL. The density gradient profile of plasma lipoproteins showed that the concentrations of VLDL + IDL and LDL decreased during the first week of postnatal life, whereas HDL concentration increased sharply around hatching and remained stable afterwards. All plasma lipoprotein classes of the newborn chick (2 days from hatching) were enriched in cholesterol and cholesteryl esters; 2 weeks after hatching, the relative amount of cholesterol and cholesteryl esters decreased. In the newborn chick, plasma VLDL + IDL consisted of two populations of cholesteryl ester-rich lipoproteins: the main one (designated apoB-VLDL) contained apoB and no apoA-I; the other (designated apoA-I-VLDL) contained predominantly apoA-I. In the newborn chick there was an accumulation of free and esterified cholesterol in the liver and, to a lesser extent, in the skeletal muscle. These cholesterol deposits were depleted 2 to 7 days after hatching. The depletion in skeletal muscle was preceded by and associated with a striking increase in the synthesis of apoA-I in this tissue, as demonstrated by immunological methods and apoA-I mRNA measurements. In addition, apoA-I-containing HDL were secreted in vitro by explants of skeletal muscle of the newborn chick. The synthesis of apoA-I in the skeletal muscle decreased to the level found in the adult animal 1 week after hatching. It is likely that the rise of HDL and apoA-I in plasma observed 1-2 days after hatching reflects the production of apoA-I-containing HDL by skeletal muscle. We suggest that the cholesterol overload in skeletal muscle might stimulate the production of apoA-I which, in turn, would promote the removal of cholesterol from this tissue. The hypothesis that metabolic stimuli play a role in inducing apoA-I synthesis in skeletal muscle is supported by the observation that feeding the newborn chick a diet rich in proteins and lipids and free of carbohydrates delays the fall of apoA-I mRNA which normally occurs 1 week after hatching.

Animals↗
PubMed1989

[Plasma dehydroepiandrosterone sulfate and urine steroid excretion in hepatic cirrhosis].

In the present study we evaluated the alterations of plasma levels of dehydroepiandrosterone sulphate (DHEA-S) and of steroid-derivatives urinary excretion in cirrhotic patients compared with normal controls. 107 patients have been studied: 45 affected by liver cirrhosis (22 males and 23 females) both in compensated and in ascitic state, and 62 healthy controls (32 males and 30 females). In all patients we assayed plasma DHEA-S by RIA as well as common liver function tests; moreover gaschromatographic profile of adrenal steroid excretion was performed in daily urine. Our findings show a significantly lower DHEA-S in cirrhotic patients compared with healthy controls, both males (451.7 SD 440.3 ng/ml vs 1438.3 SD 604.8, p less than 0.001) and females (225.5 SD 152.6 ng/ml vs 974.0 SD 405.7, p less than 0.001). Variance analysis confirmed that the difference was significant both for compensated and uncompensated ones. We also found some interesting relationships between DHEA-S and liver function tests, cholesterol and age. Urinary steroids were markedly low in both sexes, particularly adrenal sexual fraction. Our data show clear disfunction in DHEA-S metabolism in liver cirrhosis, partially related with the severity of the disease.

Adult↗
PubMed1989

Expression of the myeloperoxidase gene in acute and chronic myeloid leukemias: relationship to the expression of cell cycle-related genes.

The expression of the myeloperoxidase (MPO) gene was studied, by means of Northern blot analysis in 14 cases of acute myeloid leukemia (AML), 11 cases of chronic myeloid leukemia (CML), and 6 cases of CML blast crisis, and in HL60 cells before and after induction of terminal differentiation with retinoic acid (RA), phorbol esters (TPA), or vitamin D. The expression of a panel of cell cycle-related genes, namely C-MYC, histone H3, ornithine decarboxylase, P53, vimentin, and calcyclin, was also studied in the same cell populations. Our results indicate that: (a) MPO gene expression (steady state mRNA levels) is strictly confined to the first stages of myeloid differentiation, reaching its peak at the promyelocyte stage and becoming undetectable in mature granulocytes and monocytes; (b) cells devoid of any detectable MPO enzymatic activity such as leukemic basophils have a high content of MPO mRNA; and (c) MPO gene expression is not related to the growth activity of the cell population. Finally, our results show that the pattern of expression of growth-regulated genes in the neoplastic myeloid disorders AML, CML, and CML blast crisis is remarkably different.

Blast Crisis↗
PubMed1989

Increased erythrocyte membrane arachidonate and platelet malondialdehyde (MDA) production in psoriasis: normalization after fish-oil.

Evidence exists of platelet activation and increased thromboxane B2 production in psoriasis. In 13 patients suffering from psoriasis, we determined the lipid composition of erythrocyte membrane, erythrocyte and platelet glutathione peroxidase activity (E-GSH-Px; Plt-GSH-Px), platelet MDA production and bleeding time. Compared with normal controls, psoriatics showed a significant increase in erythrocyte membrane arachidonic acid (AA) (p less than 0.001) and polyunsaturated fatty acids (PUFA) (p less than 0.001), platelet MDA production (p less than 0.01) and E- and Plt-GSH-Px activity (p less than 0.01; p less than 0.01). After 8 weeks of fish-oil supplementation (20 ml/day) we observed the following changes: a) marked amelioration of skin lesions; b) normalization of membrane lipid pattern and platelet MDA production; c) a further increase in E- and Plt-GSH-Px activity (p less than 0.01; p less than 0.01); d) significant prolongation of bleeding time (p less than 0.05). Our data demonstrate: 1) a generalized perturbation of membrane lipid pattern in psoriasis, characterized by an excess of AA; 2) an activation of AA metabolism in platelets suggested by increased MDA production and GSH-Px activity; 3) dietary fish-oil may normalize membrane lipid pattern and reduce platelet hyperactivity in psoriasis.

Adult↗
PubMed1989

Philadelphia-positive chronic myelogenous leukemia with typical bcr/abl molecular features and atypical, prolonged survival.

Despite the major breakthrough in the knowledge of the molecular events underlying the t(9;22) translocation, still no consistent data have been found on the evolution of Ph1 positive CML from the chronic to the accelerated or blastic phase of the disease. In most patients in fact the bcr/abl rearrangements are identical both in chronic phase and in blast crisis, and overall differences in chronic phase duration, related to different location of breakpoints inside the bcr region, were found to be marginal. We approached this problem by studying the molecular features of the bcr/abl abnormality in rare CML patients with very long, atypical chronic phase. The three patients studied, whose chronic phase duration is 17, 19, and 21 years, respectively, have typical genomic bcr rearrangements, and two of them show, hybridizing Northern blots to c-abl, the 8.5 kb mRNA, as that typically present in CML. It seems that genomic alterations within bcr and abl cannot account, alone, for the duration of the chronic phase of Ph1 positive CML and those quantitative and/or qualitative alterations of the p210 bcr/abl protein, unluckily awkward to prove, might be responsible for the atypical clinical features of these CML long survivors.

Adult↗