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Biomedical subjects

C Caruso

Publications and source records attributed to C Caruso.

At least 19 recordsLinked to original sources
PubMed1992

Thermostable NAD(+)-dependent alcohol dehydrogenase from Sulfolobus solfataricus: gene and protein sequence determination and relationship to other alcohol dehydrogenases.

The NAD(+)-dependent alcohol dehydrogenase (EC 1.1.1.1) from the thermoacidophilic archaebacterium Sulfolobus solfataricus, DSM1617 strain (SSADH), has been purified and characterized. Its gene has been isolated by screening two S. Solfataricus genomic libraries using oligonucleotide probes. The encoding sequence consists of 1041 base pairs, and it shows a high preference for codons ending in T or A. The primary structure, determined by peptide and gene analysis, consists of 347 amino acid residues, yielding a molecular weight of 37,588. A level of identity of 24-25% was found with the amino acid sequences of horse liver, yeast, and Thermoanaerobium brockii alcohol dehydrogenases. The coenzyme-binding and catalytic and structural zinc-binding residues typical of eukaryotic alcohol dehydrogenases were found in SSADH with the difference that one out of the four structural zinc-binding Cys residues is substituted by Glu. The protein contains four zinc atoms per dimer, two of which are removed by chelating agents with a concomitant loss of structural stability.

Alcohol Dehydrogenase↗
PubMed1992

Haemoglobin of the antarctic fish Pagothenia bernacchii. Amino acid sequence, oxygen equilibria and crystal structure of its carbonmonoxy derivative.

The Antarctic fish Pagothenia bernacchii has one major haemoglobin, Hb1 (over 95% of the total blood content). Hb1 has a strong alkaline Bohr effect and at low pH exhibits the reduced ligand affinity and co-operativity that comprise the Root effect. We have determined the complete amino acid sequence of P. bernacchii Hb1 and also the structure of its carbonmonoxy derivative by X-ray crystallography, to a resolution of 2.5 A. The crystallographic R-factor of the refined structure is 18%. The three-dimensional structure of this fish haemoglobin is similar to that of human haemoglobin A, with a root-mean-square difference in main-chain atom positions of 1.4 A after superimposition of the two structures, despite only 48% homology of their amino acid sequences (including insertion of a single residue in the CD region of the fish alpha-chain). Large structural differences occur only at the N and C termini of both the alpha- and beta-chains. Neither these nor other smaller structural differences provide any obvious explanation of the Root effect of this or other fish haemoglobins.

Amino Acid Sequence↗
PubMed1992

The effect of age on mitogen responsive T cell precursors in human beings is completely restored by interleukin-2.

It is well known that the function of T lymphocytes is significantly impaired by advancing age. In the present study, attempts have been made to further characterize the T cell impairment of elderly subjects. Thus, we have performed limiting dilution microculture analysis to evaluate the precursor frequency of T lymphocytes responding to a mitogenic stimulus in old and young subjects. Furthermore we have evaluated the activity of recombinant interleukin-2 (rIL-2) on these cells. The results demonstrate that in older subjects the frequency of these precursors is significantly decreased. The in vitro treatment with rIL-2 increased the frequency of mitogen responsive T lymphocyte precursors in both groups so that the difference between the two groups was not significant. Thus present results extend the findings demonstrating that older subjects display an impairment of T cell functions and that IL-2 treatment may correct these alterations. In particular, they confirm the hypothesis that age-associated functional changes are more likely due to diminished numbers of reactive cells, than to a decline in the activity of all cells.

Adult↗
PubMed1992

The amino acid sequence of the single hemoglobin of the high-antarctic fish Bathydraco marri Norman.

1. Bathydraco marri Norman is a cold-adapted Antarctic teleost (Family: Bathydraconidae), living preferably at depths between 400 and 1200 m. 2. The blood of this species contains a single hemoglobin, in which oxygen binding is pH-regulated (Bohr and Root effects). 3. The complete amino acid sequence of the alpha and beta chains of the hemoglobin of B. marri has been elucidated.

Acylation↗
PubMed1992

[Laparoscopic cholecystectomy: analysis of first 203 cases].

Laparoscopic cholecystectomy is a valid alternative to open cholecystectomy. The Authors present their experience in the management of 208 consecutive patients. The low incidence of complications, the short hospital stay as well as earlier return to work, and lower medical expenses are the advantages of laparoscopic surgery. The latter is, therefore, more suitable for the treatment of benign gallbladder diseases.

Cholecystectomy↗
PubMed1992

Blood antiphospholipid antibody levels are influenced by age, sex and HLA-B8,DR3 phenotype.

Antiphospholipid antibodies (APA) are known to be associated with a number of seemingly heterogeneous pathological conditions that are part of the antiphospholipid syndrome, formerly called anticardiolipin syndrome. Recent studies on the mechanism of action of these autoantibodies suggest that we are dealing with a new autoimmune syndrome which may occur either in a primary form or in the context of other autoimmune diseases, mainly systemic lupus erythematosus (SLE). Moreover, increased levels of APA have been found in elderly subjects, who are known to display increased frequency of autoimmune phenomena. It is well known that many autoimmune diseases, including SLE, are associated with HLA antigens, particularly with HLA-B8,DR3 phenotype. In our study, APA serum levels were analyzed in 26 old subjects and in 56 young ones. The results demonstrate that HLA-B8,DR3-positive young females display significantly higher levels of APA than HLA-B8,DR3-negative ones. Interestingly, the same is true for elderly subjects on the whole with respect to young individuals. These data are consistent with previous findings demonstrating that HLA-B8,DR3-positive subjects (mainly female) as well as old subjects display (also in the absence of any clinical manifestation), multiple immune dysfunctions that may underlie the predisposition to autoimmunity.

Adult↗
PubMed1991

The hemoglobins of the cold-adapted Antarctic teleost Cygnodraco mawsoni.

The blood of the teleost Cygnodraco mawsoni, of the endemic Antarctic family Bathydraconidae, contains a major hemoglobin (Hb 1), accompanied by a minor component (Hb 2, about 5% of total). The two hemoglobins have identical alpha chains and differ by the beta chain. The complete amino acid sequence of the three chains has been elucidated, thus establishing the primary structure of both hemoglobins. The sequences show a 53-65% identity with non-Antarctic poikilotherm fish species; on the other hand, a very high degree of similarity (83-88%) has been found between Hb 1 and the major component of another Antarctic species of a different family. The hemoglobin functional properties relative to oxygen binding have been investigated in intact erythrocytes, 'stripped' hemolysate and purified components of C. mawsoni. The hemoglobins display the Bohr and Root effects, indicating fine regulation of oxygen binding by pH and by the physiological effectors organic phosphates.

Adaptation, Physiological↗
PubMed1991

Soluble interleukin-2 receptor release defect in vitro in elderly subjects.

The evidence from several studies indicates that as individuals age, they may display immune dysfunctions, mostly T cell dysfunctions. Recently, a soluble form of the receptor for interleukin-2 (IL-2) (sIL-2R) has been demonstrated in human sera and in vitro stimulated culture supernatants from human T lymphocytes. In the present paper, we report in vitro sIL-2R production from peripheral blood mononuclear cells in elderly subjects. The results show that no difference exists for unstimulated cultures, whereas after mitogen stimulation the elderly subjects showed the lowest values compared with young ones. These findings suggest that sIL-2R may provide a new tool for the study of T lymphocyte dysfunctions in old age.

Aged↗
PubMed1991

Effect of nickel on oxygen free radical metabolism. Inhibition of superoxide dismutase and enhancement of hydroxydopamine autoxidation.

The effect of nickel on superoxide dismutase activity (SOD), as well as on rate of hydroxydopamine oxidation, was studied in vitro since lipid peroxidation has been implicated in cell damage by nickel, whose toxicity and carcinogenicity are well established. Nickel strongly inhibits SOD activity. The degree of inhibition is directly proportion to the nickel concentration (tested range 0.066 to 0.33 microgram/mL in the reaction mixture); to the substrate concentration (tested range 0.4 x 10 4M to 1.1 x 10 4M 6-hydroxydopamine); and to reaction mixture. Autoxidation of 6-hydroxydopamine was increased by nickel concentrations higher than 15 micrograms/mL. The combination of excessive oxygen free radical production and inhibition of their elimination by inhibition of SOD activity may contribute to the nickel toxicity that has been reported in industrial accidents, as well as to the high incidence of cancer occurring in nickel workers. It may also contribute to many complications in uremic patients, in whom increased serum nickel levels were reported to be in a similar range to those inhibiting SOD.

Free Radicals↗
PubMed1991

HLA-B8,DR3 T cell impairment is completely restored by in vitro treatment with interleukin-2.

The activity of recombinant interleukin-2 (rIL-2) on the in vitro lymphocyte proliferative response to phytohemagglutinin mitogen was investigated in healthy HLA-B8,DR3 positive and negative subjects. The response to mitogen, significantly decreased in HLA-B8,DR3 positive subjects, was completely restored by adding rIL-2. Moreover, in HLA-B8,DR3 positive subjects the in vitro treatment with rIL-2 significantly increased the reduced frequency of mitogen responsive T lymphocyte precursors, as assessed by limiting dilution analysis. These data suggest that a decrease in the size of the pool of T cell precursors able to produce IL-2 is responsible for the impairment of T cell function observed in HLA-B8,DR3 positive subjects. Since in autoimmune diseases it is possible to show the same impairment(s) of T cell functions which can be observed in HLA-B8,DR3 positive subjects, these results could be of practical value for the understanding of pathogenetic mechanism(s) of autoimmune diseases and, in case, for therapeutical purposes.

Adult↗
PubMed1991

Effect of aluminum on calcium binding to bovine intestinal calcium-binding protein.

Aluminum is known to inhibit vitamin D-dependent intestinal absorption of calcium. To investigate possible mechanisms of action, the effect of aluminum on the binding of calcium to bovine intestinal calcium-binding protein (CaBP) was studied by means of equilibrium dialysis. The results of these studies indicate that aluminum in concentrations up to 80 microM and up to 80 times the ambient calcium concentration did not significantly alter the affinity of CaBP for calcium (Kd = 0.17 microM) nor its molar capacity (2 mol/mol CaBP).

Aluminum↗
PubMed1991

Immunoglobulin heavy-chain allotypes play a role in the clinical history of celiac disease.

We studied the role of the immunoglobulin heavy-chain allotypes in the evolution of celiac disease. Particularly the Gm(fb) phenotype was investigated since this phenotype is able to determine the breadth of immune response against alpha-gliadin antigen. The results show that weight percentiles and intestinal absorption as assessed by xylose test are influenced by Gm(fb) phenotype suggesting that Gm(fb) genes contribute to the determination of clinical aspects and evolution of celiac disease.

Adolescent↗
PubMed1991

Effect of chromium on oxygen free radical metabolism, inhibition of superoxide dismutase and enhancement of 6-hydroxydopamine oxidation.

The effect of chromium on superoxide dismutase activity (SOD) as well as on the rate of hydroxydopamine oxidation was studied in vitro, since chromium is known as an environmental and occupational carcinogen and oxygen free radicals are implicated in carcinogenic processes. Chromium is a strong inhibitor of SOD activity in this system. The degree of inhibition is directly proportional to the chromium concentration (tested chromium range 0.166-0.33 mg/L in reaction mixture), to reaction time (tested range up to 10 minutes), and to substrate concentration. Autoxidation of 6-hydroxydopamine was increased by chromium concentration of 15 mg/L. The combination of excessive oxygen free radical production and inhibition of their elimination by inhibition of SOD activity may contribute to the toxic effects of chromium.

Ascorbic Acid↗
PubMed1991

Immunoglobulin heavy chain allotypes in a sample of Sicilian patients with celiac disease.

The authors have studied the immunoglobulin heavy chain allotypes in 14 Sicilian patients with celiac disease (CD) and in 75 healthy controls. No association has been found between CD and Gm or Km phenotypes. When the role of Gm phenotypes in immune response against gliadin was analyzed, fb-positive CD patients on gluten-free diet for 1 year showed an increased antigliadin IgG response. Comparing the values of fb-positive subjects with those of negative ones, a significant difference was observed. These data, demonstrating that the presence or absence of a phenotype is able to define the breadth of immune response against alpha-gliadin antigen, are indicative of the role played by Ig allotypes in CD.

Adolescent↗
PubMed1990

The amino terminal sequence of the developmentally regulated Ch21 protein shows homology with amino terminal sequences of low molecular weight proteins binding hydrophobic molecules.

Ch21 protein, a developmentally regulated chick embryo protein of 21,000 apparent molecular weight, was purified from culture medium of hypertrophic chondrocytes. The purification method included a DEAE cellulose chromatography column, a CM cellulose chromatography column and a HPLC molecular sieve column. The amino acid sequence of the amino terminal end of the protein was determined. Computer assisted analysis showed significant homology between this sequence and the amino terminal sequences of proteins that belong to the superfamily of the low molecular weight binding proteins sharing a basic framework for the binding and transport of small hydrophobic molecules. Determination of the amino terminal sequence of the chicken retinol binding protein excluded identity between this protein and the Ch21.

Amino Acid Sequence↗