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S Ferrari

Publications and source records attributed to S Ferrari.

At least 55 records · Page 3Linked to original sources
PubMed1990

Complement-mediated demyelination in patients with IgM monoclonal gammopathy and polyneuropathy.

We investigated the role of complement in the pathogenesis of the demyelinating polyneuropathy that occurs in some patients with IgM monoclonal gammopathy. Seven patients with chronic sensorimotor polyneuropathy and IgM monoclonal gammopathy were examined. In six patients, the monoclonal protein recognized an epitope shared by myelin-associated glycoprotein and two peripheral-nerve glycolipids, whereas in one patient, IgM bound to an unidentified myelin antigen. Direct and indirect immunofluorescence and immunoperoxidase assays showed colocalization along the myelin sheaths of peripheral-nerve fibers of monoclonal protein with complement components C1q, C3d, and C5. In addition, terminal-complement complex that was not associated with S protein was detected in myelin sheaths. It appeared that alterations in myelin geometry caused by the separation of myelin lamellae corresponded to sites at which terminal-complement complex was deposited. We conclude that demyelination in polyneuropathy associated with IgM monoclonal gammopathy may be mediated by complement.

Aged↗
PubMed1990

Transmembrane cation fluxes and fatty acid composition of erythrocytes in psoriatic patients.

Cation transport systems and lipid composition of erythrocyte membrane were studied in 27 psoriatic patients and in 34 healthy individuals. Whereas intracellular Na and K content, Na- and K-passive permeability and Li-Na countertransport of psoriatics did not show any statistical difference from normals, the Na/K ATPase pump activity was significantly higher and Na-K cotransport was significantly lower. Membrane lipid composition of psoriatics was different from normals: an increase in arachidonic acid and in unsaturated (poly- and total unsaturated) fatty acid content was found. A positive correlation was demonstrated between unsaturated/saturated fatty acid ratio and Na/K ATPase pump activity. These results demonstrate an alteration of erythrocyte Na/K ATPase pump and Na-K cotransport in psoriasis. These alterations of cation transport are associated with a perturbation of membrane fatty acid composition which appears a widespread phenomenon in cells of psoriatic patients.

Adult↗
PubMed1990

Differentiation-dependent expression of apolipoprotein A-I in chicken myogenic cells in culture.

Northern blot hybridization experiments showed that Apolipoprotein A-I (Apo A-I) mRNA is present at high concentration in chicken myotubes cultured in vitro, while it is virtually absent in fibroblasts and myoblasts. Myotubes are also capable of translating and secreting in the culture medium a protein which is specifically immunoprecipitated by anti-Apo A-I antibodies and has the same electrophoretic mobility as Apo A-I purified from circulating high-density lipoproteins. The appearance of Apo A-I mRNA in myotubes depends on the transcriptional activation of the corresponding gene, as it was shown by hybridizing 32P-labeled RNA synthesized in isolated nuclei to Apo A-I cDNA. The activation of the Apo A-I gene is regulated by the muscle cell coordinately with muscle-specific genes. In fact, treatment with TPA, a powerful inhibitor of differentiation, efficiently prevents myoblasts from producing Apo A-I mRNA, as well as muscle actin mRNA, and causes myotubes to quickly cease Apo A-I mRNA synthesis. The existence of a strict relationship between Apo A-I mRNA concentration and myogenic cell differentiation was also confirmed by experiments with quail myoblasts transformed with a temperature-sensitive mutant of the Rous Sarcoma Virus. Cells raised at the permissive temperature (undifferentiated phenotype) do not contain Apo A-I as well as alpha-actin mRNAs, while shifting to the nonpermissive temperature (differentiated phenotype) causes a rapid increase in Apo A-I and alpha-actin mRNA concentration.

Actins↗
PubMed1990

Overexpression of the MPO gene occurring in a case of APL without unusual genotypic characteristics.

Northern blot analysis of four typical cases of acute promyelocytic leukemia showed that one of the cell population examined was characterized by a very high level of expression of the myeloperoxidase (MPO) gene. Western blot analysis confirms that the protein content of the cells corresponded to the levels of the MPO mRNA. Southern blot studies of the DNA of this cell population ruled out the presence of any genome amplification or rearrangement. Chromosome hybridization studies in situ confirmed that the MPO gene was translocated on the long arm of chromosome 15. The observation that a typical genomic pattern may or may not be associated with the MPO overexpression leads us to believe that so far it is impossible to reach any conclusion about the significance of the translocation in the genesis of MPO overexpression.

Blotting, Southern↗
PubMed1990

Cloning of the mitogen-activated S6 kinase from rat liver reveals an enzyme of the second messenger subfamily.

Recently we reported the purification of a mitogen-activated S6 kinase from Swiss mouse 3T3 fibroblasts and rat liver. The rat liver protein was cleaved with cyanogen bromide or trypsin and 17 of the resulting peptides were sequenced. DNA primers were generated from 3 peptides that had homology to sequences of the conserved catalytic domain of protein kinases. These primers were used in the polymerase chain reaction to obtain a 0.4-kilobase DNA fragment. This fragment was either radioactively labeled and hybridized to Northern blots of poly(A)+ mRNA or used to screen a rat liver cDNA library. Northern blot analysis revealed four transcripts of 2.5, 3.2, 4.0, and 6.0 kilobases, and five S6 kinase clones were obtained by screening the library. Only two of the clones, which were identical, encoded a full-length protein. This protein had a molecular weight of 56,160, which correlated closely to that of the dephosphorylated kinase determined by SDS/PAGE. The catalytic domain of the kinase resembles that of other serine/threonine kinases belonging to the second messenger subfamily of protein kinases.

Amino Acid Sequence↗
PubMed1990

The importance of dose-intensity in neoadjuvant chemotherapy of osteosarcoma: a retrospective analysis of high-dose methotrexate, cisplatinum and adriamycin used preoperatively.

The relationship between dose-intensity and outcome was retrospectively analyzed in 125 patients with osteosarcoma of the extremities treated at our institution with neoadjuvant chemotherapy between 1986 and 1988. Before surgery, chemotherapy was performed with high-dose methotrexate (HDMTX) i.v. followed by cisplatinum (CDP) i.a. and adriamycin (ADM) i.v. Postoperative chemotherapy was tailored according to the necrosis induced by preoperative treatment. Patients who were "good responders" had 31-weeks of chemotherapy with the same drugs utilized preoperatively, while "poor responder" patients received a longer treatment (40 weeks) in which ifosfamide and etoposide (VP-16) were added to HDMTX, CDP and ADM. At a median follow-up of 2 years (1-3 years) 100 patients (80%) remained continuously disease-free and 25 patients relapsed: 24 with lung metastases and 1 with local recurrence. According to the real dose-intensity received, calculated as a percentage of the dose intensity projected by the protocol, the continuously disease-free survival was 87% in the 82 patients who received 80% or more of the scheduled dose-intensity and only 65% for the 43 patients who received less than 80% of the projected dose-intensity. This difference is highly significant (P less than 0.01). These results suggest that in neoadjuvant chemotherapy of osteosarcoma the real dose-intensity delivered is a determinant of treatment outcome and therefore every effort should be made to avoid reductions of doses and delays of cycles of chemotherapy in these patients.

Adolescent↗
PubMed1990

Cell membrane lipid composition in CAPD patients.

We analyzed the erythrocyte membrane lipid composition in 11 non-diabetic CAPD patients on treatment for 3-78 months and in a control group of 12 subjects. The mean total values of both saturated fatty acids and unsaturated fatty acids were not statistically different in CAPD patients and in controls but the composition of fatty acids of in cell membranes was altered. In fact, CAPD patients had a higher percentage of monounsaturated fatty acids and a lower percentage of polyunsaturated fatty acids than controls. This increase MUFA/PUFA ratio might reflect either a preferential cell membrane uptake of MUFA or a relative PUFA deficiency due to an increased lipid peroxidation.

Aged↗
PubMed1990

Modification of serum and membrane lipid composition induced by diet in patients with chronic renal failure.

Disorders of lipid metabolism during chronic renal failure (CRF) play a crucial role in the pathogenesis of early cardiovascular complication of this syndrome. In addition, some experimental evidence suggests that hyperlipidemia may accelerate progression of renal disease. We have studied 65 patients with CRF (S-creatinine 1.5-9.0 mg/dl), 52.3% of whom were hypertensive. Patients were divided in 2 groups matched for age, sex and degree of renal failure: group 1 was kept for 36 +/- 8 months on a free diet; group 2 was kept for 39 +/- 6 months on a low-protein diet with an elevated polyunsaturated/saturated fatty acid (PUFA/SFA) ratio. We found significantly higher levels of triglycerides (TG) and lower levels of esterified cholesterol in high density lipoprotein (HDL-C) in group 1 than in group 2. Patients on the diet had a lower percentage of membrane SFA and a higher percentage of PUFA than patients on free diet. Only in group 1 a direct correlation between cholesterol/phospholipid (Chol/P) ratio and age was observed; in group 2, a negative correlation between levels of PUFA and TG and between linoleic/oleic (Lin/Ol) ratio and serum Chol was shown. S-creatinine levels were directly correlated with Chol/P ratio in group 1 and indirectly with Lin/Ol ratio and PUFA in group 2. These data show that a low-protein diet, containing an elevated PUFA/SFA ratio, is able to counteract lipid abnormalities in patients with CRF and the normalization of this pattern is associated with significant improvement of membrane lipid composition and, presumably, of "functional" activity of cell membranes with a better control of supposed "renal lipoprotein toxicity".

Adult↗
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↗