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P Pucci

Publications and source records attributed to P Pucci.

153 records · Page 9Linked to original sources

[Prognostic significance of the intraventricular blocks during acute myocardial infarction (author's transl)].

An intraventricular conduction defect complicated 39 out of 489 cases of acute myocardial infarctions. The defect, with the exception of one case, always developed in infarctions in the anterior wall of the heart. Compared with the other acute anterior myocardial infarctions in which the mortality in the Coronary Care Unit was 15%, infarctions complicated by intraventricular conduction defects have on the whole, presented a worse clinical course and a higher mortality rate (56%). It must be stressed that clinical course and mortality rate have been very different in the various conduction defects. The most innocuous conduction defects were the left anterior hemiblock, and, with some reservation, the right bundle branch block too, -- defects in which the clinical course and the mortality rate were not significantly different from those of the other anterior myocardial infarctions not complicated by intraventricular conduction troubles. On the contrary clinical course was more serious and mortality rate higher (50%) in the cases in which the two defects were associated. Myocardial infarctions complicated by left bundle branch block, right bundle branch block with left posterior hemiblock, alternating bundle branch block or 1 degrees and 2 degrees atrioventricular block and bundle branch block, presented an extremely serious clinical course and a very high mortality rate (83%). These differences in the clinical course and in the mortality rate of the various intraventricular conduction defects are explained by the fact that they are associated with myocardial damage of different degree, which is clarified by knowledge of the blood supply of the intraventricular conduction system.

Acute Disease↗

Substance P inactivation by transglutaminase in vitro.

Gamma(glutamyl5)spermine derivative of substance P (Spm-SP) was synthesized in vitro in the presence of purified guinea pig liver transglutaminase and Ca2+. The spermine adduct of the neuropeptide was purified by HPLC on a reversed-phase column and characterized by fast atom bombardment mass spectrometry. The biological activities of Spm-SP were tested by assaying, in comparison with substance P, its ability to induce both the contractions of smooth muscle in vitro and the edema formation in vivo. Spm-SP was shown not to elicit contractile responses in the isolated rat stomach strip and duodenum and not to antagonize the spasmogenic effect evoked by the native neuropeptide. Furthermore, Spm-SP was unable, when administered into rats by plantar injection, either to provoke an acute inflammatory response in the hind limb or to antagonize the edema formation induced by a concurrent administration of substance P. These results indicate that the introduction of a large size hydrophilic moiety at the glutamine5 level negatively affects the ability of the neuropeptide to bind to its receptor(s), thus supporting the view that the hydrophobic middle portion of substance P plays a key role in receptor recognition.

Amino Acid Sequence↗

River buffalo (Bubalus bubalis L.) AA phenotype haemoglobins: characterization by immobiline polyacrylamide gel electrophoresis and high performance liquid chromatography and determination of the primary structure of the constitutive chains by mass spectrometry.

1. Polyacrylamide gel electrophoresis in ultra-narrow immobilized pH gradient shifted the "Hb fast" band of AA buffalo phenotype haemoglobin into two components which were named Hb1 and Hb3. 2. Urea/Triton electrophoresis and reversed-phase HPLC demonstrated that Hb1 and Hb3 differ in the presence of two structurally distinct alpha chains (alpha 1 and alpha 3), also suggesting that the alpha chains must differ for neutral amino acid substitution. 3. Extensive mass spectrometric analysis on several digests (FAB overlapping) meant to determine the complete sequence of the constituent chains. 4. Two amino acid replacements (Lys 18----His and Asn 116----His) were present in the beta chain with respect to the bovine (A phenotype) chain, whereas the alpha 1 and alpha 3 globins were found to contain four amino acid replacements compared to the bovine alpha, three of which were identical (Glu 23----Asp, Glu 71----Gly and Phe 117----Cys) and, notably, an insertion of Ala at position 123-124. 5. Furthermore, alpha 1 contains Phe at position 130 whereas alpha 3 contains Ser at position 132 (following the modified numbering as a consequence of the Ala insertion).

Acrylamides↗

Electrospray mass spectrometric analysis of river buffalo (Bubalus bubalis) hemoglobins. Re-examination of alpha 1 and alpha 3 globin chain sequences.

1. The accurate molecular weight of the globin chains from river buffalo hemoglobin components has been determined by means of electrospray mass spectrometry. 2. The ES/MS analysis demonstrated that all the buffalo Hb components share a common beta chain whose mass value coincides with that expected on the basis of the reported sequence. 3. The AA phenotype alpha 1 and alpha 3 globin chains exhibited a 30 Da mass difference as compared to their predicted molecular weights. Careful re-examination of the two alpha globin sequences by FAB/MS revealed the occurrence of sequence errors and hence the correct primary structure of both alpha chains was established.

Amino Acid Sequence↗

Clinical, biochemical and therapeutical aspects of amiodarone-induced hypothyroidism (AIH) in geriatric patients with cardiac arrhythmias.

The clinical features and the laboratory aspects of the amiodarone-induced hypothyroidism (AIH) in the elderly as well as the effects of amiodarone treatment in aged AIH people have not yet been well clarified. In the present paper, we evaluated 18 subjects of both sexes (7 females, 11 males), aged 65-83 years, affected by AIH, recruited in Central Tuscany, Italy. The patients were divided in two subsets on the basis of thyroid stimulating hormone (TSH) values: mild (TSH < 20 mU/l; Group A, n=11) and severe (TSH > 20 mU/l; Group B, n=7) hypothyroid patients. On the basis of clinical features, hypothyroidism was diagnosed only in two patients (out of Group B). Concerning the hormonal pattern, we found that free tetraiodothyronine (fT4) levels were significantly lower than the normal range only in Group B subjects; TSH and thyroglobulin were higher than normal in both groups; free triiodothyronine (fT3) were always in the normal range. Thyroid autoantibodies were found positive only in one patient out of Group A and in two patients out of Group B. In 5/18 patients T4 substitutive therapy was rapidly assigned, because of severe degree of hypothyroidism. In the remaining 13/18 patients, we evaluated the clinical behavior of AIH. After additional cardiac evaluation, amiodarone was withdrawn in 5/13 patients: during follow-up period (4-10 months) four patients became quickly euthyroid while one worsened. In 8/13 patients, amiodarone treatment had to be carried on; during follow-up (2-48 months), four patients remained mildly hypothyroid, while other four patients became severely hypothyroid. In conclusion, in amiodarone treated elderly people, diagnosis of hypothyroidism is reliable only on the basis of high values of TSH; clinical features and fT3 serum levels never enable diagnosis.

Aged↗

Novel autocrine and paracrine loops of the stem cell factor/chymase network.

BACKGROUND: The aim of this study was to investigate whether the secretory granules of human mast cells store stem cell factor (SCF). We also addressed the question whether mast cell chymase, a chymotrypsin-like protease, also present in the secretory granules of human mast cells cleaves SCF at the peptide bound between Phe 158 and Met159. METHODS: The skin samples were obtained from patients with mastocytosis, undergoing skin biopsy for diagnostic purposes. Mast cells were isolated and purified from human lung parenchyma (human lung mast cells, HLMC) by countercurrent elutriation followed by discontinuous Percoll density gradient. SCF contents of human mast cells were assessed for immunoreactive SCF by ELISA. Western blot analysis of SCF and its cleavage products were performed with the MoAb anti-SCF 7H6. SCF and its proteolytic fragment were characterized by electrospray mass spectrometry (ES/MS). RESULTS: SCF is present in the secretory granules of human skin and lung mast cells. Immunoreactive SCF (iSCF) was detected in the cell lysates of HLMC, but not in basophils. iSCF was rapidly (3 min) released after challenge with anti-IgE, and iSCF in supernatants rapidly declined after 30 min. ES/MS analysis of rhSCF1-166 treated with recombinant human chymase showed a polypeptide of 17,977.1+/-0.6 Da and a minor component of 697.4+/-0.1 Da generated by specific cleavage at Phe159. SCF1-166 and SCF1-159 similarly activated HLMC and potentiated anti-IgE-induced activation of these cells. The cleavage product SCF160-166 had no effect on mast cells. Western blot analysis of supernatants of anti-IgE activated HLMC incubated for various intervals with rhSCF1-166 showed that rhSCF1-166 was converted to a faster-migrating form with a molecular weight compatible with SCF1-159 and to several SCF species. CONCLUSION: SCF is stored in human mast cell secretory granules and is immunologically released by mast cells. SCF1-166 is rapidly cleaved by chymase and other proteases to several SCF species.

Autocrine Communication↗