1
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Vittori M, Signoretti M, Cipriani C, Bertolo R, Gasparoli C, Antonucci M, Maiorino F, Carilli M, Iacovelli V, Petta F, Panei M, Travaglia S, Filippi B, Vicentini C, Ferraro P, Bove P. Probiotics together with potassium citrate and magnesium reduce crystalluria in patients undergoing endourological surgery for stone disease: Report from a pilot study. Eur Urol 2023. [DOI: 10.1016/s0302-2838(23)01262-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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2
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Mazzon G, Ferretti S, Acquati P, Nazzani S, Campobasso D, Germinale F, Filippi B, Micali S, Pavan N, De Marco G, Vismara Fugini A, Morena T, Peroni A, Celentano G, Creta M, Serafin E, Costa G, Rocco B, Maestrani U, Vaccaro C, Carmignani L, Trombetta C, Cerruto M, Antonelli A, Celia A. The effect of COVID-19 outbreak on endourological treatments for urinary stones: A retrospective multicentric study. Eur Urol 2022. [PMCID: PMC9155269 DOI: 10.1016/s0302-2838(22)00335-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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3
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Bozzini G, Berti L, Maltagliati M, Besana U, Calori A, Filippi B, Sighinolfi M, Micali S, Buizza C, Rocco B. Laparoscopic partial nephrectomy with thulium laser enucleation of the tumor: perioperative and functional outcomes. EUR UROL SUPPL 2021. [DOI: 10.1016/s2666-1683(21)00948-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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4
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Filippi B, Sighinolfi M, Pescuma A, Ferrari R, Ticonosco M, Di Pietro C, Fidanza F, Saraceni G, Bianchi G, Rocco B, Micali S. 30-Days complication rate of renal stone treatments: a retrospective single center analysis on 298 patients. EUR UROL SUPPL 2021. [DOI: 10.1016/s2666-1683(21)00869-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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5
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Bonfante G, Ciarlariello S, Sarchi L, Calcagnile T, Assumma S, Filippi B, Pescuma A, Rassweiler J, Gozen A, Silay S, Puliatti S, Eissa A, Bozzini G, Sighinolfi M, Bianchi G, Rocco B, Micali S. Investigating the spread of en bloc resection for bladder cancer in daily practice among IEA and ESUT members. EUR UROL SUPPL 2021. [DOI: 10.1016/s2666-1683(21)00701-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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6
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Bozzini G, Maltagliati M, Berti L, Besana U, Calori A, Cassani A, Filippi B, Sighinolfi M, Buizza C, Micali S, Rocco B. Xray and US free calix puncture before PCNL (XUF PCNL): a comparison with standard Xray/US guided puncture. EUR UROL SUPPL 2021. [DOI: 10.1016/s2666-1683(21)00777-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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7
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Kostadinova R, Filippi B, Moritz W, Pajak A, Sanchez K, Wolf A. Steatosis as risk factor for drug-induced liver injury (DILI). Toxicol Lett 2021. [DOI: 10.1016/s0378-4274(21)00627-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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8
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Bozzini G, Filippi B, Alriyalat S, Calori A, Besana U, Mueller A, Pushkar D, Otero J, Pastore A, Sighinolfi M, Micali S, Buizza C, Rocco B. Disposable versus reusable ureteroscopes: A prospective multicenter randomized comparison. EUR UROL SUPPL 2020. [DOI: 10.1016/s2666-1683(20)35417-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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9
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Sighinolfi M, Sarchi L, Ticonosco M, Filippi B, Assumma S, Calcagnile T, Morini E, Bonfante G, Sandri M, Puliatti S, Amato M, Micali S, Bianchi G, Maiorana A, Bonetti L, Rocco B. The Prediction of extracapsular extension of prostate cancer: First external validation study of the PRECE model. EUR UROL SUPPL 2020. [DOI: 10.1016/s2666-1683(20)35369-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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10
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Iseppi A, Guarino G, Filippi B, Toso S, Paterlini M, Sighinolfi M, Bozzini G, Micali S, Bianchi G, Rocco B. Evaluation of PSA density for the detection of clinically significant prostate cancer in biopsy-naive patients with PI-RADS 3 lesions. EUR UROL SUPPL 2020. [DOI: 10.1016/s2666-1683(20)35366-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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11
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Filippi B, Sighinolfi M, Sarchi L, Morini E, Moschovas M, Toso S, Seetharam B, Rocco B, Patel V. Oncotype DX genomic prostate score and final tumor pathology: A new instrument in pre-radical prostatectomy counseling. EUR UROL SUPPL 2020. [DOI: 10.1016/s2666-1683(20)35368-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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12
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Sighinolfi M, Eissa A, Rizzo M, Iseppi A, Morini E, Filippi B, Reggianibonetti L, Torricelli P, Sandri M, Micali S, Bianchi G, Rocco B. Multiparametric magnetic resonance imaging (mpMRI): Which variable better predicts extracapsular extension of prostate cancer? EUR UROL SUPPL 2020. [DOI: 10.1016/s2666-1683(20)30039-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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13
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Morini E, Marzotta L, Sighinolfi M, Filippi B, Del Prete C, Iseppi A, Eissa A, Reggiani B, Rizzo M, Torricelli P, Sandri M, Paterlini M, Micali S, Bianchi G, Rocco B. Correlation between mpMRI-detected lesions and definite neoplastic foci at radical prostatectomy: Level of agreement in terms of size and proximity to the capsule. EUR UROL SUPPL 2020. [DOI: 10.1016/s2666-1683(20)30044-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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14
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Borin G, Filippi B, Moroder L, Santoni C, Marchiori F. Kinetic and conformational studies on some partially synthetic ribonuclease S' analogues modified in position 8. Int J Pept Protein Res 2009; 10:27-38. [PMID: 881290 DOI: 10.1111/j.1399-3011.1977.tb02773.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Syntheses are described of two S-peptide analogues where the arginyl residue in position 10 has been replaced by ornithine and the phenylalanine in position 8 has been substituted by the unnatural amino acids cyclohexylalanine or p-fluorophenylalanine. In order to regenerate the arginyl residue, which is present in position 10 in the natural sequence, the S-peptide analogues beloning to the [Orn10]-series are transformed into the corresponding guanidinated derivatives by treatment with O-methylisourea. 1epsilon, 7epsilon, 10delta triguan-[Cha8, Orn10]-, 1epsilon, 7epsilon, 10delta-triguan-[pF-Phe8, Orn10]- and 1epsilon, 7epsilon, 10delta-triguan-[Tyr8, Orn10]-S-peptides were prepared. The ability to bind to and activate the S-protein of the synthetic S-peptide analogues, before and after guanidination, was tested by exploring their capacity to generate ribonuclease activity using RNA and C greater than p as substrates. The affinity of the different peptides for the S-protein in the absence of substrate was evaluated by difference spectroscopy.
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15
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Abstract
We investigated the structural effects induced by Al3+ on different beta-amyloid (Abeta) fragments at pH 7.4 and T=25 degrees C, with particular attention given to the sequences 1-40 and 1-42. Al3+ caused peptide enrichment in beta sheet structure and formation of solvent-exposed hydrophobic clusters. These intermediates evolved to polymeric aggregates which organized in fibrillar forms in the case of the Al3+-Abeta(1-42) complex. Comparative studies showed that Zn2+ and Cu2+ were much less efficient than Al3+ in stimulating the spontaneous aggregation/fibrillogenesis of Abetas. Studies with liposomes as membrane models showed dramatic changes in the structural properties of the lipid bilayer in the presence of Al3+-Abeta complexes, suggesting a major role of Al3+ in Abeta-induced cell dysfunction. Al3+ effects were abolished by desferrioxamine mesylate (DFO) only in solution. We concluded that, in vivo, DFO may act as a protective agent by preventing or reverting Abeta aggregation in the extracellular spaces.
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Affiliation(s)
- F Ricchelli
- CNR Institute of Biomedical Technologies, Metalloproteins Unit, Department of Biology, University of Padova, Viale G. Colombo, 3-35121, Padova, Italy
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16
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Abstract
Using spectroscopic techniques we studied the effect of the nucleophilic reagents cyanide, cyanate and thiocyanate on three flavo-oxidases namely alcohol oxidase (AO), glucose oxidase (GOX) and D-amino acid oxidase (DAOX). All three ions, added at concentrations in the mM range, caused release of the flavin adenine dinucleotide (FAD) co-factors from the enzyme molecules. In the case of AO this was accompanied by significant conformational perturbations, which was not observed for GOX and DAOX. As suggested from fluorescence, absorption and circular dichroism spectral changes at least one phenolic hydroxyl group became ionized upon FAD release from AO and a new class of Trp residues, fluorescent only in apo-AO protein, was demasked.
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Affiliation(s)
- T Zlateva
- Department of Molecular Biology, University of Padua, Italy
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17
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Biasiolo A, Rampazzo P, Furnari O, Filippi B, Pengo V. Comparison between routine laboratory prothrombin time measurements and fingerstick determinations using a near-patient testing device (Pro-Time). Thromb Res 2000; 97:495-8. [PMID: 10704660 DOI: 10.1016/s0049-3848(99)00191-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- A Biasiolo
- Department of Clinical and Experimental Medicine, Thrombosis Center, University of Padova School of Medicine, Padova, Italy
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18
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Boteva R, Visser AJ, Filippi B, Vriend G, Veenhuis M, van der Klei IJ. Conformational transitions accompanying oligomerization of yeast alcohol oxidase, a peroxisomal flavoenzyme. Biochemistry 1999; 38:5034-44. [PMID: 10213606 DOI: 10.1021/bi982266c] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Alcohol oxidase (AO) is a homo-octameric flavoenzyme which catalyzes methanol oxidation in methylotrophic yeasts. AO protein is synthesized in the cytosol and subsequently sorted to peroxisomes where the active enzyme is formed. To gain further insight in the molecular mechanisms involved in AO activation, we studied spectroscopically native AO from Hansenula polymorpha and Pichia pastoris and three putative assembly intermediates. Fluorescence studies revealed that both Trp and FAD are suitable intramolecular markers of the conformation and oligomeric state of AO. A direct relationship between dissociation of AO octamers and increase in Trp fluorescence quantum yield and average fluorescence lifetime was found. The time-resolved fluorescence of the FAD cofactor showed a rapid decay component which reflects dynamic quenching due to the presence of aromatic amino acids in the FAD-binding pocket. The analysis of FAD fluorescence lifetime profiles showed a remarkable resemblance of pattern for purified AO and AO present in intact yeast cells. Native AO contains a high content of ordered secondary structure which was reduced upon FAD-removal. Dissociation of octamers into monomers resulted in a conversion of beta-sheets into alpha-helices. Our results are explained in relation to a 3D model of AO, which was built based on the crystallographic data of the homologous enzyme glucose oxidase from Aspergillus niger. The implications of our results for the current model of the in vivo AO assembly pathway are discussed.
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Affiliation(s)
- R Boteva
- Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia
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19
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Genov N, Goshev I, Nikolova D, Georgieva DN, Filippi B, Svendsen I. A novel thermostable inhibitor of trypsin and subtilisin from the seeds of Brassica nigra: amino acid sequence, inhibitory and spectroscopic properties and thermostability. Biochim Biophys Acta 1997; 1341:157-64. [PMID: 9357954 DOI: 10.1016/s0167-4838(97)00049-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A novel thermostable protein inhibitor of trypsin and subtilisin, called BN, was isolated from the seeds of Brassica nigra. The purified protein gave a single band on SDS-PAGE, corresponding to a molecular mass of 15 500 +/- 1000 Da. The inhibitor is composed of two disulfide-linked polypeptide chains, consisting of 39 and 90 residues, respectively. The amino acid sequence of the two chains was determined by Edman degradation of peptides, isolated from enzyme hydrolysates with TPCK-trypsin, EndoLysC proteinase and a Glu-specific proteinase of reduced and vinylpyridinated protein samples. A segment of the 'heavy' chain, between residues 65 and 81, showed homology with the reactive site loop region of the 6-kDa trypsin inhibitors from Nicotiana alata. The basic residue in position 39 (N. alata) or 70 (napins) is conserved as arginine or lysine in all inhibitors from N. alata and in all napins hitherto sequenced. Probably, the two families of trypsin inhibitors have structurally similar reactive sites. BN exhibits an extremely high thermostability: CD measurements showed that during heating to 97 degrees C it preserves a considerable part of the polypeptide backbone folding. Studies on the fluorescence properties of the inhibitor BN in the absence and presence of neutral or ionic quenchers demonstrated that the intrinsic emission of this protein is dominated by a tryptophyl residue, buried in the interior of the protein matrix. 20% of the light absorbed by Tyr 63 of the 'heavy' chain is transferred to Trp 26 of the 'light' chain.
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Affiliation(s)
- N Genov
- Institute of Organic Chemistry, Bulgarian Academy of Sciences, Sofia
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20
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Ruzza P, Donella-Deana A, Calderan A, Filippi B, Cesaro L, Pinna LA, Borin G. An exploration of the effects of constraints on the phosphorylation of synthetic protein tyrosine kinase peptide substrates. J Pept Sci 1996; 2:325-38. [PMID: 9230460 DOI: 10.1002/psc.70] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We synthesized by classical solution methods three conformational constrained analogues of EDNEYTA, a heptapeptide sequence that represents the common major autophosphorylation site of the protein tyrosine kinases (PTKs) of the Src family. The correlation between the different structural properties induced by the modifications of the native sequence and the propensity of the peptides to act as PTK substrates was examined. The kinetic data obtained indicate that the introduction of the tyrosine-analogue constraints Tic(OH) and MeTyr, which block the ring flexibility, completely prevents the phosphorylation catalysed by the kinases Lyn and Fgr. On the other hand PTKIIB/p38syk can phosphorylate the two derivatives albeit with an efficiency lower than that found with the native sequence. A third derivative contained side chain to side chain cyclization. This analogue, in which the freedom of the phenolic moiety is not altered, can be phosphorylated by all the PTKs tested with kinetic constants comparable to the parent peptide.
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Affiliation(s)
- P Ruzza
- CNR, Biopolymers Research Centre, Department of Organic Chemistry, University of Padua, Italy
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21
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Malerba M, Boni E, Tantucci C, Filippi B, Romagnoni G, Grassi V. Ineffectiveness of intravenous beta 2-agonists on improving exercise tolerance in patients with reversible chronic airway obstruction. Respiration 1996; 63:8-16. [PMID: 8833987 DOI: 10.1159/000196509] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The effects on exercise tolerance after acute administration of beta 2-agonists were investigated in 11 patients with partly reversible chronic airway obstruction after 400 micrograms of salbutamol (S) given intravenously (i.v.) and after 400 micrograms i.v. of a new selective beta 2-agonist, broxaterol (B), by a cardiopulmonary incremental exercise test. At rest, while VE increased in respect to basal conditions (C) after S (from 13.3 +/- 2.2 to 14.4 +/- 2.8 l/min; p < 0.05) and after B (from 13.6 +/- 3.1 to 15.5 +/- 3.6 l/min; p < 0.05), VO2, VCO2 and VO2/HR showed no substantial variations. A small, not significant reduction of PaO2 was observed both after S (from 82.7 +/- 11.7 to 79.1 +/- 16.7 mm Hg) and B (from 81.6 +/- 10.5 to 78.0 +/- 11.0 mm Hg). The maximum workload increased neither after S (from 67.5 +/- 39.1 to 66.6 +/- 37.0 W) nor after B (from 65.7 +/- 39.3 to 60.0 +/- 35.8 W). At peak of exercise, VO2, VCO2 and VO2/HR did not change after S and B as compared with C, whereas VE remained higher after both beta 2-agonists throughout the effort. VO2 at ventilatory anaerobic threshold (AT) was significantly greater either after S (from 744 +/- 378 to 815 +/- 302 ml/min; p < 0.05) and after B (from 756 +/- 290 to 842 +/- 292 ml/min; p < 0.05). The PaO2 increase shown by these patients during effort was greater after beta 2-agonists administration, delta PaO2 from rest to peak of exercise amounting to 14.9 +/- 14.3 vs. 7.8 +/- 8.2 mm Hg after S and to 17.8 +/- 15.1 vs. 8.8 +/- 10.9 mm Hg after B, in respect to relative baseline (p < 0.05). We conclude that beta 2-agonists, when given acutely, do not improve exercise tolerance in patients with reversible chronic airflow obstruction, although these drugs can induce a small increment of ventilatory AT. In addition, arterial blood gases do not deteriorate at rest and are better preserved during exercise after beta 2-agonists.
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Affiliation(s)
- M Malerba
- Clinica di Medicina Interna I, University of Brescia, Italy
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22
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Roggero MA, Filippi B, Church P, Hoffman SL, Blum-Tirouvanziam U, Lopez JA, Esposito F, Matile H, Reymond CD, Fasel N. Synthesis and immunological characterization of 104-mer and 102-mer peptides corresponding to the N- and C-terminal regions of the Plasmodium falciparum CS protein. Mol Immunol 1995; 32:1301-9. [PMID: 8643099 DOI: 10.1016/0161-5890(95)00136-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We investigated the immunogenicity and the conformational properties of the non-repetitive sequences of the Plasmodium falciparum circumsporozoite (CS) protein. Two polypeptides of 104 and 102 amino acids long, covering, respectively, the N- and C-terminal regions of the CS protein, were synthesized using solid phase Fmoc chemistry. The crude polypeptides were purified by a combination of size exclusion chromatography and RP-HPLC. Sera of mice immunized with the free polypeptides emulsified in incomplete Freund's adjuvant strongly reacted with the synthetic polypeptides as well as with native CS protein as judged by ELISA and IFAT assays. Most importantly, these antisera inhibited the sporozoite invasion of hepatoma cells. In addition, sera derived from donors living in a malaria endemic area recognized the CS 104- and 102-mers. Conformational studies of the CS polypeptides were also performed by circular dichroism spectroscopy showing the presence of a weakly ordered structure that can be increased by addition of trifluoroethanol. The obtained results indicate that the synthetic CS polypeptides and the natural CS protein share some common antigenic determinants and probably have similar conformation. The approach used in this study might be useful for the development of a synthetic malaria vaccine.
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Affiliation(s)
- M A Roggero
- Institute of Biochemistry, University of Lausanne, Epalinges, Switzerland
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23
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Ruzza P, Calderan A, Filippi B, Biondi B, Deana AD, Cesaro L, Pinna LA, Borin G. Linear and cyclic synthetic peptides related to the main autophosphorylation site of the Src tyrosine kinases as substrates and inhibitors of Lyn. Int J Pept Protein Res 1995; 45:529-39. [PMID: 7558583 DOI: 10.1111/j.1399-3011.1995.tb01316.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Tyrosine protein kinases (TPKs) of the src family contain two major phosphoacceptor sites which are homologous to the Tyr 416 and Tyr 527 of pp60c-src. The former represents the main autophosphorylation sites of these enzymes, and its phosphorylation correlates with increased kinase activity. It has previously been demonstrated that the Src-like tyrosine kinase expressed by the oncogene lyn displays a high affinity toward the heptapeptide H-Glu-Asp-Asn-Glu-Tyr-Thr-Ala-OH, which reproduces the main autophosphorylation site of the Src family enzymes [Donella-Deana, A., Marin, O., Brunati, A.M. & Pinna, L.A. (1992) Eur. J. Biochem. 204, 1159-1163]. Our study was addressed to the synthesis of some derivatives of this sequence in order to obtain both peptide substrates suitable for the detection of the Src-like tyrosine kinase activity and active site-directed inhibitors specific for this class of enzymes. For this purpose we synthesized by classical solution methods the heptapeptide and its dimeric form. Moreover, in order to improve the proteolytic resistance of these peptides we also synthesized their cyclic derivatives and their N-terminal acetylated and C-terminal amidated analogs. The correlation between the different structural properties induced by the modifications of the native sequence and the propensity of the peptides to act as Lyn substrates was examined. The kinetic data obtained indicate that the extent of the peptide phosphorylation varies considerably depending on the flexibility and length of the analogs. While the cyclization and the C-terminal amidation of the heptapeptide are detrimental for the Lyn activity, dimeric derivatives display very favourable kinetic constants. In particular the cyclic dimer is an especially suitable substrate for the tyrosine kinase and a powerful inhibitor of both the phosphorylation activity of Lyn and the enzyme autophosphorylation.
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Affiliation(s)
- P Ruzza
- CNR, Department of Organic Chemistry, University of Padua, Italy
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24
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Abstract
The stability towards thermal and chemical (guanidine hydrochloride, GnHCl) denaturation of six inhibited subtilases (mesentericopeptidase, subtilisins BPN', Carlsberg and DY, proteinase K and thermitase) has been investigated by kinetic and equilibrium studies. The unfolding processes were monitored by circular dichroic and fluorescence spectroscopy. Experiments in the absence and presence of extraneous calcium in the concentration range 2 x 10(-3)-10(-1) M were performed. The presence of calcium in the weak calcium binding site changes the denaturation drastically. The heat- (or GnHCl-) induced unfolding curves obtained using CD spectroscopy show two independent transitions which seem not to have been resolved before. The presence of Ca2+ in the second (third in the case of thermitase) binding site increases the Tm values by 11-21 degrees C and the delta GD(H2O) values obtained from denaturation experiments in GnHCl by 6.7-7.2 kcal/mol when an extraneous Ca2+ concentration of 2 x 10(-2) M was used. One interpretation is that the initial step of denaturation in the presence of added calcium is the formation of a partially unfolded intermediate form, retaining a highly ordered structure with 60-85% of the alpha-helix structure of the native enzyme. This intermediate then unfolds at a temperature considerably higher than that of the same proteinases in the absence of added Ca2+. The free energy of stabilization of the intermediates is increased by 1.8-2.8 times in comparison with that for the unfolding reactions of the subtilases with empty Ca2/Ca3 binding sites. A second interpretation is that the two steps in the unfolding curves correspond to enzyme without and with calcium in the weak binding site. Fluorescence experiments confirm the mechanism involving the formation of intermediate states. The results are discussed in relation to the X-ray models of the six subtilases.
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Affiliation(s)
- N Genov
- Institute of Organic Chemistry, Bulgarian Academy of Sciences, Sofia
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25
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Malerba M, Boni E, Romagnoni G, Filippi B, Politi A, Giustina A, Tantucci C, Grassi V. Effects of beta 2-agonists during cardiopulmonary exercise test in COPD patients. Monaldi Arch Chest Dis 1994; 49:389-93. [PMID: 7841973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The aim of this study was to evaluate endocrine-metabolic, respiratory and cardiovascular effects of two beta 2-sympathomimetic selective agents, such as broxaterol and salbutamol, before and during cardiopulmonary exercise test (CPX). Twelve in-patients with chronic obstructive pulmonary disease (COPD) (with partially reversible airways obstruction) were included. Broxaterol (400 micrograms) and salbutamol (400 micrograms) were administered i.v., according to a double-blind, cross-over study. Before treatment and within 60 min after the administration of each agent, the patients underwent incremental CPX by bicycle ergometer to the maximum tolerable threshold. At these times the following variables were assessed: minute ventilation (VE), oxygen consumption (VO2), carbon dioxide production (VCO2), VE/VO2 ratio and O2 pulse, glycaemia, insulinaemia, plasma norepinephrine (NE) and epinephrine (E), arterial oxygen and carbon dioxide tension (PaO2 and PaCO2), plasma lactates, heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressure. Spirometry was performed before and after the administration of each beta 2-adrenoceptor agonist. CPX brought about a significant increase in VE, VO2, VCO2, and O2 pulse. Broxaterol or salbutamol administration did not significantly modify the increases caused by CPX. At rest, 60 min after treatment, both bronchodilators caused a significant rise in glycaemia. A significant reduction of PaO2 (after broxaterol) and PaCO2 (after salbutamol) was observed at rest. In contrast, both agents caused no modification to potassium and insulin levels.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M Malerba
- Dept of Internal Medicine I, University of Brescia, Italy
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Abstract
The present paper reports how aluminium [Al(III)] at a concentration of 3.7 microM can activate the bovine erythrocytic enzyme acetylcholinesterase (AChE) by about 38% in vitro. This same activating effect was observed on AChE form human as well as from rat erythrocyte ghosts and murine neuroblastoma cells. The interaction between Al3+ and gamma-peripheral sites of the enzyme produces AChE structural modifications as evidenced by circular dichroism measurements. This may provide a molecular explanation of the raised enzymatic activity.
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Affiliation(s)
- P Zatta
- Center CNR-Metalloproteins, University of Padova, Department of Biology, Italy
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Filippi F, Panarese P, Filippi B, Muzio G, Raposio E. [Etiopathogenesis of hand syndactyly in the light of several experimental findings]. Pediatr Med Chir 1993; 15:437-41. [PMID: 8159576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The limb developmental program is comprised of processes of cell multiplication and of cell determination, differentiation and morphogenesis. Many of these processes depend on cell-cell communications within tissues and between different tissue types. The Authors present a review of the more significant data about the etiology of the syndactylies of the hand, both in their physiopathogenic aspects and in their clinical typology. The peculiarity of these malformations is outlined, supported by literature data and personal experimental experiences.
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Affiliation(s)
- F Filippi
- Cattedra di Chirurgia Plastica e Ricostruttiva, Università degli Studi di Genova, Italia
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29
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Ruzza P, Calderan A, Filippi B, Donella-Deana A, Pinna LA, Borin G. Synthesis and conformational studies on peptides corresponding to a putative autophosphorylation site of abl TPK. Int J Pept Protein Res 1993; 41:291-9. [PMID: 8463052 DOI: 10.1111/j.1399-3011.1993.tb00337.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The transforming gene of Abelson murine leukaemia virus (v-abl) codes for a membrane-associated tyrosine-specific protein kinase (abl TPK). Analysis of the v-abl gene has shown that both the fibroblast-transforming and tyrosine-protein kinase activities reside within a minimal region encoding a protein of 43 kDa (p43v-abl), which represents the most active, isolated form of this enzyme. Since the cellular substrates for p43v-abl are yet to be identified, we synthesized by classical solution methods the octapeptide H-Gly-Asp-Thr-Tyr-Thr-Ala-His-Ala-OH, corresponding to the structural sequence of the main putative autophosphorylation site (Tyr 515) of the abl TPK, as well as some of its analogs modified in positions -2, -1, +1 and +3. The synthetic peptides were tested as substrates for the p43v-abl. The kinetic data obtained indicate that the rates of their phosphorylation vary considerably depending on the sequence of the peptide, as expected. As a rule, no significant increment of the efficiency results from each substitution in the parent sequence. While the replacement of the two charged residues, namely Asp-2 and His-7, with neutral Ala is well tolerated, the substitution with amino acids bearing opposite charges is detrimental. The correlation between secondary structure of our synthetic octapeptides and their substrate recognition by p43v-abl was studied using CD and fluorescence spectroscopy in 5 mM Tris, in 98% TFE/Tris and in 30 mM SDS solutions. The comparison of the spectroscopic data with the kinetic parameters does not confirm a close relationship between the conformational properties of these peptides and their enzymatic role.
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Affiliation(s)
- P Ruzza
- CNR Centre for the Study of Biopolymers, Department of Organic Chemistry, University of Padua, Italy
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Malerba M, Politi A, Filippi B, Zambruni U, Grassi V. [Changes in the heart rhythm and slow-release beta-2 agonist therapy (peroral) in asthmatic patients. A Holter study]. Recenti Prog Med 1992; 83:665-71. [PMID: 1494703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Slow-release formulations of salbutamol, used in asthmatic patients, may have few effects on cardiac rhythm. This study was designed to compare incidence and type of cardiac arrhythmias in a group of ten patients with stable bronchial asthma before and after 6 weeks treatment with a slow-release formulation of salbutamol. After a baseline spirometric and electrocardiographic evaluation, patients received placebo for a two-weeks period. At the end of this period patients repeated spirometry and carried out a 24-hour-ambulatory-E-Holter-monitoring. Subsequently, patients received for 6 weeks a treatment with a slow-release formulation of oral salbutamol. At the end of this period patients repeated spirometry, a 24-hour-ambulatory-EG-Holter-monitoring and potassium serum levels were controlled. We concluded from our study that, in patients with moderate bronchial asthma the treatment with an oral formulation of slow-release salbutamol may carry out a significant and durable bronchodilator effect, without causing important cardiac arrhythmias.
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Affiliation(s)
- M Malerba
- Cattedra di Medicina interna I, UOP Scienze mediche, Università, Brescia
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Cardo PP, Muzio G, Romano S, Filippi B. Testosterone metabolism in squamous cell carcinomas. Pathologica 1984; 76:599-603. [PMID: 6527896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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Filippi B, Biondi L, Filira F, Rocchi R. Synthesis of N alpha-, and C alpha-derivatives of (D)Ala2, Leu5-enkephalin. Farmaco Sci 1983; 38:713-24. [PMID: 6641923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Some (D)Ala2, Leu5-Enkephalin derivatives containing hydrophilic or hydrophobic moieties have been synthesized by the solution method. Improvement in the analgesic effect was achieved by increasing the hydrophilicity of the parent compound through covalent linkage of the 2-deoxy-D-glucopyranosyl residue to the carboxyl terminal amide nitrogen of leucine 5. Reductive glucosamination of (D)Ala2, Leu5-Enkephalin practically abolishes activity and increase in hydrophobicity lowers the potency of the parent compound in both the in vitro and in vivo tests.
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Romano S, Giomi L, Sorice G, Bertoglio C, Faravelli L, Filippi B. [Critical study of augmentation mastoplasty. Revision of case records]. MINERVA CHIR 1983; 38:909-11. [PMID: 6888752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Sorice G, Giomi L, Romano S, Bertoglio C, Filippi B. [Chemico-physical and structural study of various types of breast prostheses. Considerations on their fibrogenic potential]. MINERVA CHIR 1983; 38:881-3. [PMID: 6350934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Filippi B, Biondi L, Filira F, Rocchi R, Bellini C, Sarto G. Synthesis and biological activity of (D)Ala2,Leu5-enkephalins containing hydrophilic or hydrophobic moieties. Biopolymers 1983; 22:575-8. [PMID: 6370327 DOI: 10.1002/bip.360220170] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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36
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Ricchelli F, Jori G, Filippi B, Boteva R, Shopova M, Genov N. Effects of pH and urea on the conformational properties of subtilisin DY. Biochem J 1982; 207:201-5. [PMID: 6818946 PMCID: PMC1153849 DOI: 10.1042/bj2070201] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Subtilisin DY is very resistant to the denaturing action of urea: the conformational properties are not affected up to 4.5 M-urea, and even in the presence of 8 M-urea there is only a slow loss of ordered structure and caseinolytic activity. C.d. and fluorescence-emission studies also show that this proteinase is stable in the 5.5-10.0 pH range, whereas below pH 5.5 a sharp denaturation occurs that is complete at pH 4.5. Protein denaturation leads to a change of the emission quantum yield; in particular, in the native protein, indole fluorescence is quenched by some amino groups. Moreover, subtilisin DY possesses two classes of tyrosine residues: one class of exposed residues titrates normally, with pKapp. = 10.24, whereas one class of partially buried or hydrogen-bonded residues ionizes with pKapp. = 11.58. In general, such conformational properties resemble those of other subtilisins. However, some differences occur: e.g., subtilisin DY is less stable at acidic pH values and its tyrosine residues are more accessible to the solvent. Such differences are probably due to small variations of the three-dimensional structure; e.g., subtilisin DY has a slightly lower alpha-helix content.
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37
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Romano S, De Marini Gullaci F, Filippi B. [Incidence of basocellular and spinocellular epitheliomas in various regions of the face. Statistical review and comparison of the years 1976 and 1978]. Arch Sci Med (Torino) 1982; 139:81-82. [PMID: 7103711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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38
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Romano S, Muzio GF, Berrino P, Migliori F, Minuto F, Filippi B. [a case of monolateral megalomastia (due to receptor hypersensitivity)]. Arch Sci Med (Torino) 1982; 139:119-21. [PMID: 7103700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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39
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Battezzati M, Filippi B, Romano S, Muzio GF, Rossi FG. [Surgical treatment of epitheliomas of the lip]. MINERVA CHIR 1981; 36:589-94. [PMID: 7254566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Chessa G, Filippi B, Borin G, Moroder L, Palumbo M, Marchiori F. Inhibition of the cytochrome c/cytochrome c oxidase system by cytochrome c derivatives and related fragments. Hoppe Seylers Z Physiol Chem 1980; 361:1077-91. [PMID: 6250966 DOI: 10.1515/bchm2.1980.361.2.1077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The oxidation of ferrocytochrome c mediated by cytochrome c oxidase was investigated in the presence of ferricytochrome c, trifluoroacetyl-cytochrome c, the heme fragments Hse65-[1-65] and Hse80-[1-80] and their respective porphyrin derivatives, as well as carboxymethylated apoprotein and related fragments, polycations, salts and neutral additives. The inhibition of the redox reaction by salts and neutral molecules, even if in theoretical agreement with their effect on electrostatic interactions, may alternatively be interpreted in terms of hydrophobicity. The latter can account for the inhibitory properties of trifluoroacetylated ferricytochrome c, similar to those of ferricytochrome c. On the assumption that the inhibitory properties of some of the investigated derivatives monitor their binding affinities to the cytochrome c oxidase at the cytochrome c binding sites, the experimental results do not confirm a primarily electrostatic character for the cytochrome c/cytochrome c oxidase association process. Strong indication was found that the cytochrome c C-terminal sequence is critically involved in the complex formation. Conformational studies by circular dichroism measurements and IR spectroscopy in solution and in solid state respectively, show that some of the derivatives examined may possibly acqkuire in the binding process to the oxidase, as secondary structure similar to that present in the native cytochrome c.
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Romano S, De Marini F, Filippi B. [Malignant melanoma of the skin. Current experiences in diagnosis, histoprognostic classification and therapy]. MINERVA CHIR 1979; 34:1523-5. [PMID: 548830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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44
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Battezzati M, Filippi B, Romano S, Rossi FG. [Reconstructive surgery after exeresis of cutaneous epitheliomas of the face]. MINERVA CHIR 1979; 34:1509-16. [PMID: 548829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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45
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Marchiori F, Borin G, Filippi B, Moretto V, Bonora GM, Toniolo C. Protamines. III. Synthesis of the tetradecapeptide corresponding to the C-terminal sequence 52--65 of galline. Int J Pept Protein Res 1979; 14:143-52. [PMID: 489253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The synthesis of peptides containing blocks of arginyl residues is proposed through amidination of the corresponding ornithyl analogs. In order to test this strategy the ornithyl analog of the C-terminal sequence 52--65 of galline was synthesized by the conventional method. The amidination reaction, performed on fragments of different length and ornithyl-residue content, quantitatively converts ornithines into arginines. The strategy proposed may represent a powerful tool for the synthesis of protamines and other basic proteins.
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Filippi B, Giusti P, Cima L, Borin G, Ricchelli F, Marchiori F. Synthetic enkephalins. Addicting properties and conformational studies in solution. Int J Pept Protein Res 1979; 14:34-40. [PMID: 573753 DOI: 10.1111/j.1399-3011.1979.tb01918.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The addicting properties of [Leu5]enkephalin in mice are conserved in the LSer3 analogue and lost both in the L-Ser2 analogue and in all the L-Cha4 derivatives of the above peptides. Fluorescence measurements in water show the presence of hydrogen-bonded tyrosul OH groups in [Leu5]-enkephalin and in its LSer2 analogue. The Phe4/Cha replacements do not influence these equilibria, but they affect the near u.v. dichroism of the hydrogen bonded tyrosyl residues. In the peptide absorption region in water solution, only [Leu5]-enkephalin and its cyclohexylalnyl derivative show a positive dichroism towards high frequencies, which is maintained in 8 M ura. No clear relation is found between conformation(s) in solution and biological activity. A II' beta-turn, with residues in positions 2 and 3 at the corners, is suggested for the conformation of enkephalin bound to the receptors involved in the bioassay here used.
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47
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Toniolo C, Bonora GM, Marchiori F, Borin G, Filippi B. Protamines. II. Circular dichroism study of the three main components of clupeine. Biochim Biophys Acta 1979; 576:429-39. [PMID: 427200 DOI: 10.1016/0005-2795(79)90418-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The three main components YI, YII, and Z of clupeine, a protamine from herring, have been purified and characterized. The conformational preferences of clupeines have been examined as a funciton of pH, temperature, added salts, and presence of structure-disrupting agents and helix-supporting solvents using circular dichroism. It was found that these small basic proteins assume predominantly an unordered conformation in aqueous solution. Addition of counter ions, in particular perchlorate, and 2-chloroethanol induces in various amounts the onset of the right-handed alpha-helical conformation. Urea favors the statistical coil state. It was also demonstrated that in the 0.1--4.0 . 10(-1) M range, in contrast to clupeines YI and Z, the circular dichroic properties of the YII component do not seem to be sensitive to the addition of mono- and diphosphate.
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Filippi B, Borin G, Moretto V, Marchiori F. Conformational properties of the N-terminal residues of S-peptide. II. The guanidine hydrochloride-water-trifluoroethanol system. Biopolymers 1978. [DOI: 10.1002/bip.1978.360171103] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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49
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Valle G, Zanotti G, Filippi B, del Pra A. X-ray analysis of bovine pancreatic ribonuclease analogs: a difference Fourier at 2.8 A resolution of (Orn10)-ribonuclease S'. Biopolymers 1977; 16:1371-6. [PMID: 880361 DOI: 10.1002/bip.1977.360160618] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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50
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Filippi B, Borin G, Moroder L, Marchiori F. Near-ultraviolet difference absorption and circular dichroism studies on partially synthetic ribonucleases S'. Biochim Biophys Acta 1976; 454:514-23. [PMID: 999915 DOI: 10.1016/0005-2787(76)90277-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Near-ultraviolet difference absorption and circular dichroism (CD) spectra were recorded upon recombination of synthetic S-peptide analogs, i.e. 1epsilon, 7epsilon-diguanidino-[Tyr8]-,1epsilon,7epsilon-diguanidono-[Asn14]-, [Phe(F)8, Orn10]- and 1epsilon, 7epsilon-diguanidino-S-peptide, with S-protein. Environmental alterations of Phe-8 in the S-peptide and Tyr-25 in the S-protein, derived from the association process, lead to strong optical signals whose location and magnitude were clearly defined by means of a comparative analysis of the above spectra. Additionally, the spectroscopic effects resulting from insertion of a tyrosyl residue into an hydrophobic environment in the presence or absence of hydrogen-bonding partners were identified and compared with similar findings obtained from the model compound p-cresol.
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