Cytochrome oxidase subunit III from Arbacia lixula: detection of functional constraints by comparison with homologous sequences.

In this paper we report the comparison of the sequences of the cytochrome oxidase subunit III from three different sea urchin species. Both nucleotide and amino acid sequences have been analyzed. The nucleotide sequence analysis reveals that the sea urchin sequences obey some rules already found in mammals. The base substitution analysis carried out on the sequences of the three species pairs, shows that the evolutionary dynamics of the first and the second codon positions are so slow that do not allow a quantitative measurement of their genetic distances, thus demonstrating that also in these species the COIII gene is strongly conserved during evolution. Changes occurring at the third codon positions indicate that the three species evolved from a common ancestor under different directional mutational pressure. The multi-alignment of the sea urchin proteins indicates the existence of the amino acid sequence motif N R T that represents a possible glycosylation site. Another glycosylation site has been detected in the mammalian cytochrome oxidase subunit III, in a position slightly different. Such an analysis revealed, for the first time, a new functional aspect of this sequence.

[Rarefying osteopathy in rheumatology. Methods of evaluation and comparison of urinary hydroxyproline and serum proline iminopeptidase]. / Le osteopatie rarefacenti in reumatologia. Metodi di valutazione e confronto tra idrossiprolina urinaria eprolinoiminopeptidasi serica.

Serum proline iminopeptidase and (where possible) urinary hydroxyproline were determined in 214 subjects: normal subjects, subjects with chronic kidney disease, subjects with chronic liver disease, subjects with osteitis deformans, subjects with rheumatoid arthritis, and subjects with osteoporosis. The values of the two parameters fully corresponded. It is suggested, therefore, that proline iminopeptidase can be determined instead of hydroxyproline in cases where a primarily destructive bone disease in present.

[Sharp's syndrome. Clinical, immunological and nosographic aspects]. / La sindrome di Sharp. Studio clinico, immunologico e nosografico.

LE cells, ds-DNA antibodies (radioimmunoassay), antinuclear antibodies (ANA) by indirect immunofluorescence (IFI) and anti-ENA antibodies have been sought in 150 clinical cases observed over a 5-year period in the Rheumatology Division of Bari University. For the latter, three parallel techniques were adopted on each serum, each completed by RNA-sensitivity assay for the demonstration of anti-RNP, i.e. IFI, passive haemoagglutination (PHA) and controimmunoelectrophoresis (CIE). The series included systemic lupus erythematodes (SLE), 30 cases; rheumatoid arthritis (RA), 30 cases; progressive systemic sclerosis (PSS), 12 cases; unclassified connective tissue disease (UCTD), 8 cases; mixed connective tissue disease (MCTD), 7 cases; Sjögren's syndrome (SS), 4 cases; dermatomyositis (DM), 3 cases; overlap syndromes (PSS-SLE, SS-SLE), 2 cases; rheumatological and internal miscellanea, 54 cases, LE cells and ds-DNA antibodies were found exclusively in SLE; the anti-ENA were found in various groups of diseases, while the anti-RNP were only demonstrated in the 7 MCTD and in some SLE. Of the three techniques for demonstrating anti-ENA, the PHA proved most sensitive and CIE most specific, whereas IFI was considered most suitable for clinical screening. The clinical aspects of the 7 MCTD faithfully followed the disease picture described by Sharp, but some overlap-syndromes and the unclassified connective tissue diseases did not present anti-RNP. It is also pointed out that nephropathy is not rare in MCTD and that the clinical course of the disease is not always benign. To conclude, it is considered that MCTD merits nosographic autonomy, but further investigations are recommended for more exact nosographical typing of connective tissue diseases.

[Various forms of secondary lumbosciatic pain in children and adults]. / Su alcune lombosciatalgie secondarie dell'infanzia e dell'età adulta.

Reference is made to two personal cases in underscoring the fact that meralgia paraesthetica, though regarded as a form that displays a preference for adult males, must be considered as extended to subjects of all ages when a benign or malignant neoformation irritating the L2 root or its trunk is involved. Before classifying a case as idiopathic, therefore, one must rule out the possibility of intra-abdominal disease-usually malformative in young subjects, and benign or malignant in persons of all ages. Lastly, stress is laid on the fact that atypical lumbar and sciatic pain in the adult may be secondary to aneurysm of the abdominal aorta, the common iliacs and the hypogastric. Hence the need to look for such conditions symptomatologically.

Lineage-specific evolution of echinoderm mitochondrial ATP synthase subunit 8.

Peculiar evolutionary properties of the subunit 8 of mitochondrial ATP synthase (ATPase8) are revealed by comparative analyses carried out between both closely and distantly related species of echinoderms. The analysis of nucleotide substitution in the three echinoids demonstrated a relaxation of amino acid functional constraints. The deduced protein sequences display a well conserved domain at the N-terminus, while the central part is very variable. At the C-terminus, the broad distribution of positively charged amino acids, which is typical of other organisms, is not conserved in the two different echinoderm classes of the sea urchins and of the sea stars. Instead, a motif of three amino acids, so far not described elsewhere, is conserved in sea urchins and is found to be very similar to the motif present in the sea stars. Our results indicate that the N-terminal region seems to follow the same evolutionary pattern in different organisms, while the maintenance of the C-terminal part in a phylum-specific manner may reflect the co-evolution of mitochondrial and nuclear genes.

Evolutionary analysis of sea urchin mitochondrial tRNAs: folding of the molecules as suggested by the non-random occurrence of nucleotides.

Comparative analyses of the mitochondrial tRNA sequences of the sea urchins Arbacia lixula, Paracentrotus lividus and Strongylocentrotus purpuratus revealed that conserved nucleotides may be involved in determining the typical L-shaped spatial conformation of tRNAs. These results shed light on the specific tertiary interactions that allow the folding of the atypical mitochondrial tRNAs into a functional form. A consensus mitochondrial tRNA secondary structure was derived. It shows the presence of nucleotides virtually conserved only in these organisms that represent a sort of molecular signature in sea urchins and suggests a possible physiological role. Finally, we speculate that the non-canonical structure of animal tRNAs, as well as the deviations from the universality of the genetic code, may be due to the reduction in size of the metazoan mitochondrial genome, with the concomitant acquisition of new functions by the mitochondrial tRNAs.

Complete sequence of the mitochondrial DNA in the sea urchin Arbacia lixula: conserved features of the echinoid mitochondrial genome.

The complete nucleotide sequence (15,719 nucleotides) of the mitochondrial DNA (mtDNA) from the sea urchin Arbacia lixula is presented. The comparison of gene arrangement between different echinoderm orders of the same class provides evidence that the gene organization is conserved within the same echinoderm class. The peculiarities of sea urchin mtDNA features, already described, are confirmed by the A. lixula mtDNA sequence. The comparison of the entire sequences of mtDNA among A. lixula, Paracentrotus lividus, and Strongylocentrotus purpuratus allowed us to detect peculiar features, common to the three sea urchin species, that can represent the molecular signature of the mt genome in the sea urchin group. Analysis of the nucleotide composition indicates that A. lixula mtDNA, in contrast with the mtDNA of other sea urchins, shows a bias in the use of T and tends to avoid the use of C, most evident in the neutral part of the molecule, such as the third codon positions. This observation indicates that the three sea urchin mtDNAs evolve under different mutation pressure. Analysis of the sequence evolution allowed us to confirm the phylogenetic tree. However, the absolute divergence time, calculated on the basis of paleontological estimates, largely diverged from the expected one.

[Duodenal absorption of calcium in rats treated with 25 OHD3, diphosphonates and synthetic anabolics]. / Etude de l'absorption duodénale du calcium chez des rats traités avec 25 OHD3, avec diphosphonates et avec anabolisants de synthése.

In this study the authors developed new technics of study of duodenal absorption of calcium in rats: atomic absorption spectrophotometry, and dialysis to equilibrium. We considered that the main factors necessary for evaluation of duodenal absorption of calcium are the serum calcium, the calcium and alkaline phosphatase present in the duodenal cells and the calcium-binding proteins. The authors demonstrate that these factors are highest in rats treated with 25 OHD3 and norandrostenolone decanoate, than in control rats. In rats treated with diphosphonate, on the contrary, they obtained a reduction in the values of calcium and alkaline phosphatase contained in the duodenal cells.