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S Spada

Publications and source records attributed to S Spada.

At least 37 records · Page 2Linked to original sources
PubMed1996

[Endoscopic and histologic findings of gastric mucosa and Helicobacter pylori prevalence in patients suffering from chronic liver disease].

In this research we evaluated the prevalence of Hp in the gastric mucosa in patients suffering for chronic liver disease, either chronic hepatitis or liver cirrhosis. Sixty-three patients 27 with chronic hepatitis and 36 with liver cirrhosis, were examined by EGDS; of them we evaluated: endoscopic findings of stomach and duodenum, histology of gastric mucosa (antrum and corpus-fundus), presence of Hp in the histologic samples. We compared the positivity for Hp with the following parameters: presence of esophageal varices, macroscopic aspect of the gastric and duodenal mucosa, presence of hystological findings of gastritis, gastritis's activity, grading of the hepatic damage. In the our research we didn't point out greater prevalence of the Hp in the gastric mucosa with respect to hepatic damage, esophageal varices or macroscopic signs of gastric pathology. The Hp is significantly associated with histologic evidence of gastritis and also with the grade of gastritis's activity. The data of the present work don't suggest any correlation within the pathologic changes of the gastric mucosa caused from the liver cirrhosis and the presence or the growth of Hp.

Adult↗
PubMed1995

Co-selection of cognate antibody-antigen pairs by selectively-infective phages.

We have developed a chloramphenicol resistant derivative of fd phage with which cognate pairs of antibodies and antigens can be selected. The phage genome encodes a fusion of single-chain antibody to the C-terminal domain of gIIIp, rendering the phage non-infective. The antigen fused to the N-terminal domains of gIIIp is encoded in the same phage genome. Antigen and antibody fusion interact with each other in the periplasm of the phage-producing cell, restoring infectivity. This system has a very low background and will allow simultaneous randomisation of antibody and antigen.

Amino Acid Sequence↗
PubMed1995

A mouse Ig kappa domain of very unusual framework structure loses function when converted to the consensus.

Antibody gene sequences, particularly those of kappa light chains, are very well conserved in the framework region, and the variability is concentrated in the complementarity-determining regions (CDR). We now found that the murine antibody 93-6 (Djavadi-Ohaniance, L., Friguet, B., and Goldberg, M. (1984) Biochemistry 23, 97-104) whose Fab fragment binds the beta-subunit of Escherichia coli tryptophan synthase with high affinity (Kd of 6.7.10(-9) M) has a highly unusual kappa light chain framework, which is crucial for the function of this antibody. It carries an insertion of 8 amino acids in a conserved framework loop that faces the antigen, and its framework region 2 (FR2) which precedes CDR2 is shortened by one amino acid, normally leucine and part of an absolutely conserved beta-bulge preceding CDR2. Removal of the insertion to restore the consensus sequence reduced the binding affinity of 93-6 by a factor 3, while insertion of the missing leucine into FR2 completely abolished binding.

Amino Acid Sequence↗
PubMed1994

The role of the L-chain in ferritin iron incorporation. Studies of homo and heteropolymers.

Mammalian ferritins are 24-meric proteins composed of variable proportions of H and L-subunits. The L-chain, in contrast to the H-chain, lacks detectable ferroxidase activity, and its role in ferritin iron incorporation is unclear. In this study, apoferritins were subjected to iron loading with large iron increments to favour spontaneous iron hydrolysis. The homopolymers of the wild-type H-chain, and of a mutant H-chain with an inactivated ferroxidase centre, formed massive protein aggregates, while the L-chain homopolymers remained mostly soluble. The difference between H and L-ferritins was not related to the rate of iron oxidation or to the presence of preformed iron cores. Heteropolymers were constructed in vitro by co-renaturing different proportions of the H-chain with the L-chain or mutant H-chain with an inactivated ferroxidase centre. After loading with high iron increments, protein aggregation of the heteropolymers was reduced when the L-chain content was above 70 to 80%, either in combination with the wild-type H-chain or with the inactivated mutant H-chain. Under acidic conditions (pH 5.5, 1000 Fe atoms per molecule) the heteropolymers with about 20% H and 80% L-chains incorporated three to fourfold more iron into soluble 24-mers than the homopolymers. The data indicate that ferritins with more than 18 L-chains per molecule have the capacity to lower non-specific iron hydrolysis in bulk solution. This property is possibly due to a specific attraction of the incoming oxidized iron into the cavity and may be related to an effect of the L-chain on the cavity microenvironment. It is concluded that under high iron increments the ferritins with high L:H-chain ratios are the most efficient in incorporating iron, and this goes some way to explain why iron storage tissues contain L-rich isoferritins.

Ceruloplasmin↗
PubMed1991

Intellectual functions and personality in subjects with noncongenital myotonic muscular dystrophy.

Mental retardation and personality disorders are commonly described among the symptoms of myotonic dystrophy. Nevertheless, this tendency is not supported by systematic studies performed on large samples, whose results are controversial. We studied the cognitive functions and personalities of a group of 28 patients, in whom myotonic dystrophy had commenced in juvenile or adult life. The severity of the disease was variable, but all subjects were self-sufficient. Only 7.1% of subjects showed low intelligence with deterioration of perceptual-motor functions. This was not correlated with the severity of their disease. Women had a substantially lower mean Wechsler-Bellevue score than men. The personality function study of the entire group showed no change of psychiatric relevance but did present a depressive attitude with marked somatic concern and difficulties in establishing relationships in social life.

Activities of Daily Living↗