Biomedical subjects

C Perrucci

Publications and source records attributed to C Perrucci.

11 recordsLinked to original sources

PubMed1996

Identification of functional domains and critical residues in the adenosinetriphosphatase inhibitor protein of mitochondrial F0F1 ATP synthase.

Peptide segments of the inhibitor protein (IF1) of the F0F1 ATP synthase complex from bovine-heart mitochondria have been constructed by chemical synthesis. The IF1-(42-58)-peptide was equally effective as IF1 in inhibiting the ATPase activity of both the F0F1 complex in the mitochondrial membrane deprived of IF1 (SMP) and soluble F1. The IF1-(22-46)-peptide inhibited the ATPase activity in the soluble F1 but had no effect on either the ATPase activity or H+ conduction in SMP. Substitution of the His or Lys residues with Ala in the IF1-(42-58)-peptide decreased the inhibition of ATP hydrolysis. The inhibition exerted by the IF1-(42-58)-peptide on ATP hydrolysis in SMP exhibited a pH dependence, similar to that observed with IF1, which was lost upon replacement of His or Lys with Ala. In soluble F1, inhibition of ATP hydrolysis by IF1, the IF1-(42-58)-peptide and the IF1-(22-46)-peptide was pH dependent when F1 was first incubated with ATP. The IF1-(42-58)-peptide also caused inhibition of passive H+ conduction in SMP. This activity of the synthetic peptide was weaker, as compared to that of IF1, and practically unaffected by substitution of His or Lys with Ala. An antibody against the IF1-(42-58)-synthetic peptide stimulated ATP hydrolysis in the membrane-bound F0F1 complex with associated IF1 but was without effect on H+ conduction. An antibody against IF1 stimulated both processes.

Adenosine Triphosphate↗

PubMed1996

DCCD-sensitive proton permeability of bacterial photosynthetic membranes. Cross-reconstitution studies with purified bovine heart Fo subunits.

The DCCD-sensitive proton permeability of chromatophores, from a green strain of Rhodobacter Capsulatus is potentiometrically detected following the proton release induced by a transmembrane diffusion potential imposed by a valinomycin-mediated potassium influx with a procedure already used for bovine heart submitochondrial particles (ESMP) and vesicles from Escherichia coli (Zanotti et al. (1994) Eur. J. Biochem. 222, 733-741). In the photosynthetic system, addition of increasing amounts of DCCD inhibits, with a similar titre, both proton permeability and MgATP-dependent ATPase activity as detected in the dark. The titre for 50% inhibition coincides with that obtained measuring proton permeability and ATP hydrolysis in ESMP. Upon removal of F1, the passive proton permeability is much less sensitive to DCCD in chromatophores than in USMP, suggesting that in chromatophores the F1-Fo interaction shapes the DCCD-sensitive proton conducting pathway. Addition of the purified mitochondrial FoI-PVP and oligomycin sensitivity-conferring (OSCP) proteins to the F1 stripped chromatophores restored the sensitivity of proton permeability to DCCD detected in untreated chromatophores. Analysis of the binding of 14C[DCCD] on F1 stripped chromatophores shows that the increase of DCCD sensitivity of proton permeability, caused by addition of mitochondrial Fo proteins, is related to an increase of the binding of the inhibitor to subunit c of Fo sector of ATP synthase complex.

Animals↗

PubMed1980

[Surgical treatment, by simple suturing, in perforated gastric or duodenal ulcer. Clinico-statistical evaluation of 5 years' experience].

A series of 30 patients operated over a period of 5 yr is presented. Stress is laid on the different approaches required in relation to the progress of peritonitis, and reasons are offered for preferring suture, rather than gastroresection, vagotomy, and conservative management.

Adult↗

PubMed1980

[A case of massive hemoperitoneum caused by spontaneous detachment of epiploic appendices].

An unusual case of spontaneous detachment of the sigmoid epiploic appendix is described. The most frequently reported pathologies of these formations are reviewed. The discussion stresses the unusual clinical picture which determined the diagnostic error. Some hypotheses are also formulated on the aetiopathogenesis of ischaemia of epiploic appendices.

Adult↗

PubMed1980

[Treatment of acute cholecystitis. Clinico-statistical findings].

A series of 354 patients suffering from gall bladder and/or bile way conditions and who had undergone operation in the acute phase has been reviewed. The usefulness of early operation over more wait-and-see tactics is confirmed. Shortening of mean hospitalization is particularly significant. The difference in hospital mortality is insignificant. The only complication reported is the higher frequency of suppurative accidents in the surgical wound.

Acute Disease↗

PubMed1979

[Non-appendicular primary pathology of the large intestine as a cause of emergency surgery. Clinico-statistical evaluation of its incidence in a provincial hospital].

Reference is made to the relevant literature in a description of cases of non-appendicular primary diseases of the large intestine necessitating emergency surgery at the Tradate District Hospital over the last five years. Emphasis is placed on the wide aetiological variety of these cases, their different clinical pictures, the types of operation performed, the possible complications, and the causes of death prior to discharge.

Adolescent↗

PubMed1979