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Biomedical subjects

C Tonelli

Publications and source records attributed to C Tonelli.

25 records · Page 2Linked to original sources
PubMed1990

Sn, a light-dependent and tissue-specific gene of maize: the genetic basis of its instability.

The genetic system under investigation is defined by three major components: a gene, Sn, conferring tissue specific anthocyanin accumulation in different plant regions, light, required for color development in competent tissues, and another gene, Pl, substituting for light in its capacity to elicit pigment production. Attention is given in this paper to an Sn allele, symbolized Sn:bol3, capable of some constitutive pigmentation in seedlings and seed integuments. Sn:bol3 confers a higher pigment potential than the other alleles and is unstable. Its instability relates to its frequent changes from an original condition, indicated as Sn-s, to Sn-w, where -s and -w stand for strong and weak and refer to the two levels of seedling pigmentation. Weak derivatives arise spontaneously at a high frequency in homo- and heterozygous Sn:bol3 genotypes. In the latter, weak derivatives are also recovered on the chromosome originally devoid of Sn as if the heterozygous association had promoted "contamination" of one chromosome (recipient) with Sn coming from the other (donor). If the two chromosomes in the heterozygote are marked with contrasting alleles of R, a gene lying about two crossover units proximal to Sn, it appears that the R constitution of the recipient chromosome affects their constitution. Presence of R-r in fact leads to changes of both chromosomes in terms of Sn constitution, resulting in a majority of nonparental chromosomes, R-r Sn and r Sn-w or r sn, while replacement of R-r with R-g, a mutant derivative of R-r, leads to a drastic reduction in the yield of nonparental chromosomes.(ABSTRACT TRUNCATED AT 250 WORDS)

Alleles↗
PubMed1990

Echographic investigation in Terson's syndrome.

The authors present the A and B scan echographic images of a patient affected with Terson's syndrome. The images show the possible continuity between the vitreous hemorrhage and the hemorrhage in the optic nerve sheaths.

Humans↗
PubMed1982

Metabolism of Proline, Glutamate, and Ornithine in Proline Mutant Root Tips of Zea mays (L.).

In excised pro(1-1) mutant and corresponding normal type roots of Zea mays L. the uptake and interconversion of [(14)C]proline, [(14)C]glutamic acid, [(14)C]glutamine, and [(14)C]ornithine and their utilization for protein synthesis was measured with the intention of finding an explanation for the proline requirement of the mutant. Uptake of these four amino acids, with the exception of proline, was the same in mutant and normal roots, but utilization differed. Higher than normal utilization rates for proline and glutamic acid were noted in mutant roots leading to increased CO(2) production, free amino acid interconversion, and protein synthesis. Proline was synthesized from either glutamic acid (or glutamine) or ornithine in both mutant and normal roots; it did not accumulate but rather was used for protein synthesis. Ornithine was not a good precursor for proline in either system, but was preferentially converted to arginine and glutamine, particularly in mutant roots. The pro(1-1) mutant was thus not deficient in its ability to make proline. Based on these findings, and on the fact that ornithine, arginine, glutamic acid and aspartic acid are elevated as free amino acids in mutant roots, it is suggested that in the pro(1-1) mutant proline catabolism prevails over proline synthesis.

Journal Article↗
PubMed1976

The titre of IgG anti-A/B in the serum of group O mothers of incompatible infants with early neonatal jaundice.

The titre of IgG anti-A/B was determined by means of a 2-mercaptoethanol test in the serum of 80 blood group O mothers, who gave birth at term to A/B incompatible infants, who developed early neonatal jaundice with a serum bilirubin level of over 10 mg/100 ml. The titres were compared with the results of the direct antiglobulin test performed on the red cells from the cord blood and the necessity for exchange transfusion. Only in mothers of group A infants, a significant correlation was found between the titre of IgG anti-A and the occurrence of a positive antiglobulin test. In no case the need for an exchange transfusion was correlated with the IgG anti-A/B titre.

ABO Blood-Group System↗
PubMedDate not supplied

[Spontaneous changes in blood cholesterol and triglyceride levels in the acute phase of a stroke].

Plasma cholesterol and triglycerides concentration were determined in 32 patients with acute stroke (23 males and 9 females, mean age = 70.5 +/- 10.4 years) within the first 24 hours from the beginning of symptoms, and repeatedly afterwords, until the 22nd day. A progressive decrease of mean cholesterol concentration was observed, which reached lowest values on the 13th day (20% reduction), and stabilized afterwords. A 30% increase of mean triglycerides levels was found on the fourth day, with subsequent return to the basal level on the 13nth day. One year after, mean values of both parameters, determined in 18 patients, did not differ from the ones observed, in the same subjects, immediately after the acute event.

Acute Disease↗