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Biomedical subjects

S Formisano

Publications and source records attributed to S Formisano.

At least 55 records · Page 3Linked to original sources
PubMed1993

Structural study of rat thyroid transcription factor 1 homeodomain (TTF-1 HD) by nuclear magnetic resonance.

The 500 MHz 1H NMR spectrum of a 68-residue peptide, encompassing the rat thyroid transcription factor 1 homeodomain (TTF-1 HD), was fully assigned using standard 2D NMR methodology. The secondary structure elements and their spatial organization were determined and led to a structure very similar to that previously described for other homeodomains and expected also for TTF-1 HD from homology modeling predictions. The three-dimensional arrangement of the three helix fragments of TTF-1 HD preserves the helix-turn-helix motif commonly occurring in many classes of DNA-binding proteins.

Amino Acid Sequence↗
PubMed1993

Effect of salt concentration on TTF-1 HD binding to specific and non-specific DNA sequences.

The Thyroid Transcription factor 1 (TTF-1) recognizes specific DNA sequences by a Homeodomain (TTF-1 HD). The TTF-1 HD DNA-binding properties with both specific and non-specific DNA sequences were investigated. TTF-1 HD exists as a monomer in solution and as a monomer binds DNA. At 75 mM KCl, its relative binding affinity with a specific DNA sequence is about 50 fold higher than with a non-specific DNA sequence. Increase of KCl concentration reduces the apparent binding affinity both to specific and non-specific DNA sequences. However, non-specific binding is more sensitive than specific binding to the increase of salt concentration. When DNA-binding reactions are performed at temperature and salt concentration close to the intracellular environment, TTF-1 HD binds the specific sequence with an affinity at least 1000 fold higher respect to the non-specific sequence.

Animals↗
PubMed1993

P2 purinergic agonists and 12-O-tetradecanoylphorbol-13-acetate, as well as protein kinase A activators, stimulate thyroglobulin secretion in FRTL-5 cells.

We studied the role of various intracellular pathways in thyroglobulin secretion. The P2 agonists (ATP, ADP, GTP), 12-O-tetradecanoylphorbol-13-acetate (TPA), and protein kinase A activators stimulate thyroglobulin secretion in cells grown without TSH. The effects of these agents are additive. Pertussis toxin partially inhibits the effect of ATP but has no effect on the action of GTP. ATP and GTP increase cytosolic calcium (279 +/- 16% and 302 +/- 22%, respectively) while TPA and TSH (1 mU/ml) do not. Thus, both the protein kinase A and kinase C pathways regulate thyroglobulin secretion in FRTL-5 cells.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1993

Defect of interleukin-2 production and T cell proliferation in atopic patients: restoring ability of the CD28-mediated activation pathway.

We previously reported that T lymphocytes of atopic patients displayed a defect in CD2- and CD3-mediated pathways of cell activation; that defect relied on impairment of interleukin 2 (IL-2) production (Romano, M. F., Valerio, G., Turco, M. C., Spadaro, G., Venuta, S., and Formisono, S., Cell. Immunol. 139, 91, 1992). We have subsequently analyzed T cell response to anti-CD2, -CD3, or -CD28 monoclonal antibodies (mAb) in 40 atopic individuals, including patients subjected to immunotherapy. In the latter group T cell response to anti-CD2 mAbs was normal, while IL-2 production and proliferative response in T lymphocytes stimulated via CD3 was still impaired. Costimulation with anti-CD28 mAb rescued both IL-2 production and proliferative response in all tested patients. Response to CD28-mediated stimulation was more pronounced in atopic than that in normal individuals. Our results indicated that CD28 had a major role in T cell proliferation of atopic patients and provided a model for analyzing CD3/CD28 interactions in regulation of IL-2 gene expression.

Adult↗
PubMed1993

Evidence of a cold immunoglobulin M autoantibody against 78-kD platelet glycoprotein in a case of EDTA-dependent pseudothrombocytopenia.

Pseudothrombocytopenia is a phenomenon in which the electronic count shows spuriously low platelet counts in subjects with normal platelet levels. The mechanism of anticoagulant-dependent pseudothrombocytopenia appears to involve cold reactive agglutinins against platelet antigens. The authors report a case of EDTA-dependent pseudothrombocytopenia with evidence of a cold immunoglobulin M antibody against 78-kD platelet membrane glycoprotein (GP). Cell counts were performed by Coulter Counter S-Plus VI (Coulter, Hialeah, FL) in the following anticoagulants: EDTA, Na-citrate, and citrate-theophylline-adenosine-dipyridamole. Anti-platelet antibodies and platelet membrane GP antigens were assayed by an immunofluorescence technique as described by Van dem Borne in 1978. An immunoglobulin M/lambda anti-platelet antibody was found to react in serum as well as in plasma EDTA at room temperature, but not at 37 degrees C. This antibody appeared to be directed against GP78 membrane antigen because this antigen was not detectable by immunofluorescence in platelets collected in EDTA and Na-citrate anticoagulant, whereas a fluorescence signal was revealed in platelets collected in citrate-theophylline-adenosine-dipyridamole. This evidence was confirmed by platelet clumping inhibition tests in which target platelets were pretreated with anti-GP monoclonal antibodies. Clumping in the presence of pseudothrombocytopenia serum was inhibited by anti-GP78kD and anti-GPIIb/IIIa but not by anti-Ib. In this case, GP78 appears to be involved in platelet clumping, together with IIb/IIIa complex. The partial inhibition of the phenomenon observed in citrate-theophylline-adenosine-dipyridamole is probably related to a lower expression of the membrane antigens in platelets collected in this anticoagulant.

Agglutinins↗
PubMed1993

Experience of computer-aided management of hemapheresis unit.

Several programs are available for blood banks management but none of them is particularly made for hemapheresis. We studied a data base application able to manage any aspect of hemapheresis unit activity. The programming general criteria were: 1) easiness of use even for people without any previous experience in using Personal Computers; 2) maximum saving time in operating; 3) easily modifiable system in reply to problems or new needs; 4) automatic checks in order to have the highest automation together with the smallest error risk; 5) quick view on state of activity and on material consumption; 6) simplification of donor recruitment. After a three year long experience, we describe our program structure in order to give a basis for the development of a standardized management system which is useful for different needs and open to future applications of blood cell separators.

Blood Component Removal↗
PubMed1993

Organization and technical problems of LDL-apheresis.

The Authors consider problems related to technique and organization of LDL-Apheresis with respect to some particular aspects. They evaluate: a) Technical complexity of procedures both in devices to use and in staff preparation; b) Length of treatment which conditions the other fields of activity; c) Problems in management treatments periodicity; d) Usually high cost of this kind of procedures; e) Problems related to vascular accesses; f) Problems related to pediatric patients, both for their low weight and vascular accesses; g) Management of cardio-vascular complications; h) Difficulties in evaluation of regression of vascular lesions. Finally, it is particularly difficult the management of psychological aspects related to somatic symptoms of the disease and to the acceptance of treatment.

Blood Component Removal↗
PubMed1993

Project of computer-aided management of therapeutical apheresis.

UNLABELLED: The great increase in hemapheresis units activity that occurred during the last years caused the need for a computer-aided management (1, 2). We present a project for a data base system able to manage therapeutical apheresis (3). The program consists of five sections. a) Patient's file card: it allows to record anamnesis, examination and blood test results easily and under computer's guidance. b) Choice of therapeutic protocol: Therapeutic protocol is fixed in this section (device to be used, apheretic method, plasma volume to be processed, blood tests before and after apheresis). c) PROCEDURES: It provides procedure's data entry and guides the operator during the treatment on the ground of therapeutical protocol. d) Data processing: It allows statistics on data placed in the data base. e) Registers: It includes both a general register and the possibility of search by disease, device and method.

Blood Component Removal↗
PubMed1993

Interactions of promonocytic U937 cells with proteins of the extracellular matrix.

Monocyte interaction with proteins of the extracellular matrix (ECM) is regulated by expression of specific cell-surface receptors. 12-O-tetradecanoyl phorbol-13-acetate (TPA) has been shown to induce the promonocytic cell line U937 to a more differentiated monocyte-like state. In this study we have analysed the attachment of U937 cells to ECM proteins and the effects of treatment with TPA on this process. Non-induced U937 cells attach to fibronectin- and Matrigel-coated surfaces without TPA stimulation, but TPA further increases adherence to these substrates as measured by an enhanced binding and by the lower concentration of proteins needed in the substrate to achieve 50% of maximal cell adhesion. Attachment to type I collagen was seen only with activated U937 cells, whereas no measurable attachment to bovine serum albumin, vitronectin, and type IV collagen was detected. TPA-activated U937 cells showed a two-fold increase in the expression of the RGD-dependent integrin receptors alpha 3 and alpha 5, and a reduction in the expression of alpha 4, another fibronectin-specific receptor, whereas the common beta 1 chain was unchanged. Attachment of U937 cells to fibronectin was primarily mediated by the alpha 3 and alpha 5 integrins, as revealed by the ability of GRGDS peptides to inhibit attachment, whereas the CS-1 peptide, containing the alpha 4 binding site, was largely ineffective in blocking attachment.

Cell Adhesion↗
PubMed1992

Modulation of the carbohydrate moiety of thyroglobulin by thyrotropin and calcium in Fisher rat thyroid line-5 cells.

Thyroglobulin secreted in the medium by Fisher rat thyroid line-5 (FRTL-5) cells cultured in the presence of thyroid stimulating hormone (TSH) shows a slower electrophoretic mobility in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and a higher density position in a CsCl gradient than thyroglobulin secreted by FRTL-5 cells cultured in the absence of TSH for 5-7 days. Such a TSH effect is much less or not evident when secreted thyroglobulin is digested with peptide N-glycohydrolase F or when intracellular thyroglobulin is compared. Intracellular thyroglobulin migrates faster than thyroglobulin secreted either in the presence or in the absence of TSH. Evaluation of the mannose and galactose content of thyroglobulin demonstrates that intracellular thyroglobulin has more mannose and less galactose than extracellular thyroglobulin; it also shows that TSH decreases the mannose content of thyroglobulin while increasing its galactose content. Bio-Gel P6 chromatography shows that TSH increases the complex type carbohydrate chains while decreasing the high mannose chains in the secreted thyroglobulin. High mannose type oligosaccharides were characterized by fast atom bombardment-mass spectrometry analysis. Treatment with the calcium ionophore A23187 (5 microM) of FRTL-5 cells cultured with or without TSH causes the appearance of a "fast" migrating form of thyroglobulinin in the culture medium. Bio-Gel P6 chromatography shows that A23187 causes a dramatic decrease of the complex carbohydrate chains of the secreted thyroglobulin.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1992

Defect of CD2- and CD3-mediated activation pathways in T cells of atopic patients: role of interleukin 2.

In the present work we analyzed the proliferative response of T lymphocytes from 11 atopic patients stimulated in vitro via either the CD2 or the CD3 pathway of cell activation. In both cases we found a significant decrease of thymidine incorporation in cell DNA in comparison with T cells from normal donors. The mechanism of this impaired proliferative response was analyzed. Atopic patients' T cells were found to secrete low quantities of interleukin 2 (IL2) and to express low amounts of Tac antigen, measured as both a percentage of Tac-positive cells and a mean fluorescence intensity of Tac antigen per cell. Addition of recombinant IL2 to cultures completely restored both cell proliferative response and Tac antigen expression. This effect was specific of IL2 since addition of IL1 or IL4 did not significantly affect T cell proliferative response. We conclude that atopic patients' T lymphocytes have a defect in both CD2 and CD3 pathways of cell activation relying on impairment of IL2 production, without involving IL2 responsiveness or other lymphokine defects.

Adult↗
PubMed1991

Calcium interaction with bovine thyroglobulin: stoichiometry and structural consequences of calcium binding.

Gel filtration studies show that the thyroglobulin (Tg) molecule (dimer) binds from 18 to 50 Ca2+ ions. At pH 7.5 Tg binds 18 Ca2+ ions with a Kd of 1.3 x 10(-5) M, and 50 Ca2+ ions with a Kd of 5.5 x 10(-4) M. The binding of calcium to bovine thyroglobulin increases the absorption band of iodoamino acid residues at 315 nm. In the presence of Ca2+, the fluorescence intensity of 1-anilino-8-naphthalene sulfonate (ANS) is increased about 5-fold by Tg, with a shift in the fluorescence emission maximum from 505 to 490 nm. Thus, thyroglobulin possesses two classes of calcium binding sites with different affinities. The data reported indicate, also, that Ca2+ binding to Tg increases the hydrophobicity of the surface of the molecule.

Anilino Naphthalenesulfonates↗
PubMed1991

Treatment of severe hypercholesterolaemia by LDL-apheresis.

The most severe forms of hypercholesterolaemia scarcely respond to diet and conventional drugs administration and need, therefore, alternative treatments. Terapeutic Plasma Exchange demonstrated an improved survival of subjects with Familial Hypercholesterolaemia (FH) in spite of its limitations. Semi-selective and selective techniques have been developed in order to remove LDL cholesterol alone. We studied the efficiency in LDL removal both of membrane filtration as of dextrane sulphate adsorption on 14 FH patients, performing 302 procedures. Cholesterol extraction with the different methods was in the range of 40-65%. Mean cholesterol level was reduced from 7% to 64% depending on the protocol used. The procedures were all performed on an outpatient basis. Side effects occurred rarely and were always of not serious degree. The short and the middle term clinical effects of LDL-Apheresis are then evaluated.

Adolescent↗
PubMed1990

Regulation of the expression of the low-affinity IgE receptor (Fc epsilon RII) in the human monocyte-like cell line U-937 by phorbol esters and IgE.

The expression of the low-affinity receptor for IgE Fc epsilon RII) in the human monocyte-like U-937 cell line can be upregulated by the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) and by IgE. TPA induces terminal differentiation of U-937 cells and causes a four- to fivefold increase in the number of Fc epsilon RII. TPA also modulates the expression of several other membrane markers of U-937 cells. IgE alone has a modest effect on the expression of Fc epsilon RII (about a 10% increase), while simultaneous treatment of U-937 cells with TPA and IgE has a cooperative effect, causing an eightfold increase in the number of Fc epsilon RII. Cycloheximide strongly suppresses the expression of Fc epsilon RII, both in TPA-stimulated and unstimulated cells; this effect can be partly reversed by culturing the cells in the presence of IgE. These results suggest that TPA induces the expression of newly synthesized receptors, while IgE causes an accumulation of preformed receptors.

Antigens, CD↗
PubMed1990

Hormonal regulation of thyroid peroxidase in normal and transformed rat thyroid cells.

The hormonal induction of thyroid peroxidase (TPO) mRNA is studied in the functional rat thyroid cell line FRTL-5 and compared to the induction of thyroglobulin (TG) mRNA and I- uptake. TPO and TG mRNAs are regulated by TSH and by insulin-like growth factor I (IGF-I) and/or insulin. However, while TPO is more sensitive to TSH regulation (5- to 6-fold increase vs. 2- to 3-fold increase by IGF-I), TSH and IGF-I are equally potent in increasing TG mRNA levels (3- to 4-fold). Regulation of I- uptake appears to be different: thus TSH greatly (15-fold) increases I- uptake, while IGF-I or insulin are completely ineffective. TPO and TG mRNAs and I- transport display different sensitivity to transformation of rat thyroid cells. Thus, when another differentiated rat thyroid cell line, the PC cells, are transformed by human c-myc (PC myc), TPO and TG mRNAs are both present at normal levels, while I- uptake is slightly decreased; in the PC cells transformed by polyomavirus middle-T-antigen (PC PyMLV) TPO mRNA is undetectable and I- uptake is greatly decreased, while TG mRNA is present at normal levels. All three differentiated functions are switched off in PC cells transformed by the cooperation of c-myc and polyomavirus middle-T-antigen (PC myc + PyMLV).

Animals↗
PubMed1988

[AIDS and the community. Preliminary data of an epidemiological study].

An epidemiological study into the prevalence and incidence of anti-H.I.V. antibody seropositivity in closed communities produced preliminary data on 746 subjects, the majority of whom admitted potentially dangerous behaviour. These results demonstrated that residence in a closed community in which one can limit the use of drugs and sexual contacts reduces the risk of infection.

Acquired Immunodeficiency Syndrome↗