Biomedical subjects

C Caruso

Publications and source records attributed to C Caruso.

At least 91 records · Page 5Linked to original sources

PubMed1994

The amino acid sequence and reactive site of a single-headed trypsin inhibitor from wheat endosperm.

The sequence of a trypsin inhibitor, isolated from wheat endosperm, is reported. The primary structure was obtained by automatic sequence analysis of the S-alkylated protein and of purified peptides derived from chemical cleavage by cyanogen bromide and digestion with Staphylococcus aureus V8 protease. This protein, named wheat trypsin inhibitor (WTI), which is comprised of a total of 71 amino acid residues, has 12 cysteines, all involved in disulfide bridges. The primary site of interaction (reactive site) with bovine trypsin has been identified as the dipeptide arginyl-methionyl at positions 19 and 20. WTI has a high degree of sequence identity with a number of serine proteinase inhibitors isolated from both cereal and leguminous plants. On the basis of the findings presented, this protein has been classified as a single-headed trypsin inhibitor of Bowman-Birk type.

Amino Acid Sequence↗

PubMed1994

Daily variation in step length of trained male runners.

The purpose of this study was to quantify daily intra-individual variability in mean step length, a basic descriptor for the running pattern. Following 60 minutes of treadmill accommodation, nine trained male subjects (X age = 34.2 yrs +/- 7.2, X VO2max = 57.0 +/- 4.8 ml.kg-1.min-1) performed daily (Mon-Fri) 6-minute treadmill runs at three submaximal speeds (2.68, 3.13 and 3.58 m.s-1) over a 4-week period. To minimize extraneous influences, subjects refrained from road racing and completed the 20 running sessions (5 d.wk-1.4 weeks for each speed) at the same time of day and in the same footwear. Treadmill velocity was calibrated for each 6-minute running bout and step length was determined during the last 2 minutes of each run. Results indicated that mean step length and coefficient of variation values were 0.984 m and 2.50% at 2.68 m.s-1, 1.124 m and 2.22% at 3.13 m.s-1, and 1.254 m and 2.26% at 3.58 m.s-1. Reliability analyses indicated that the percentage of variation accounted for in step length across all speeds was high and improved very little as test number increased (range = 96% for two days vs 99% for five days). Taken together, these findings suggest that when testing conditions are controlled, within-subject variability in step length measures obtained at multiple submaximal running speeds is small in trained subjects and that criterion step length values can be obtained by averaging duplicate measurements.

Adult↗

PubMed1994

An algorithm to determine protein sequence alignment by utilizing data obtained from a peptide mixture and individual peptides.

With the aim of limiting peptide purification steps and unambiguously ascertaining protein sequences, we have designed and implemented on a personal computer an algorithm to determine sequence alignment by utilizing data obtained from automatic Edman degradation performed on a single peptide mixture and individual peptides. The protein under study is digested by two different hydrolysis methods and fragments are just isolated from one mixture and sequenced, while the second mixture is submitted unfractionated to sequence analysis. The algorithm provides for the exact alignment of the individual peptides using the mixture data for the overlapping. We report an example of application of this approach by utilizing experimental data obtained from a protein of known sequence.

Algorithms↗

PubMed1994

Hydrolysis pattern of procasomorphin by gut proteases from plant parasite Heliothis zea, determined by sequence analyses performed on the unfractionated digestion mixtures.

The digestion pattern of procasomorphin, a putative precursor of beta-casomorphins (beta-casein-derived opioid peptides), by gut proteases from the plant parasite insect Heliothis zea has been determined to evaluate the possibility of introducing in plants the gene encoding for this peptide in order to confer resistance to damage by the insect. The method we used is based on the possibility of deducing the sequence of the fragments produced by proteases at different times of digestion by means of automatic Edman degradation performed on the fragment mixtures without any purification steps. This approach can be considered of general utility in studying the digestion of peptides by a mixture of proteases.

Amino Acid Sequence↗

PubMed1994

Effect of step length optimization on the aerobic demand of running.

To assess whether distance runners displaying uneconomical freely chosen step lengths (FCSL) could be trained to shift FCSL toward a more optimal setting, six males and three females who exhibited uneconomical FCSL [mean optimal step length (OSL) = -9.81% of leg length from FCSL; mean change in oxygen uptake (VO2) (FCSL - OSL) = 1.46 ml.kg-1.min-1] comprised an experimental group that completed 15 treadmill sessions (30 min/day, 5 days/wk, 3 wk) of OSL training at individually determined running velocities (2.87-3.74 m/s). Training sessions featured alternating 5-min periods of combined audio and visual feedback matching OSL and no feedback. A control group of three subjects with uneconomical FCSL (2 males, 1 female) performed 3 wk of treadmill running without feedback. The extent of step length optimization was evaluated by comparing pre- and posttraining differences between FCSL and OSL and between pre- and posttraining VO2. Compared with the control group, the experimental group demonstrated a significantly (P < or = 0.05) greater relative shift in FCSL toward OSL and a marked reduction in FCSL VO2. Taken together, these results suggest that short-term audiovisual feedback training can be effective in optimizing step length and producing a decrease in aerobic demand among distance runners exhibiting uneconomical FCSL.

Adult↗

PubMed1994

In vitro cytokine production by HLA-B8,DR3 positive subjects.

It is well known that healthy subjects carrying the HLA-B8,DR3 haplotype may show an impairment of immune system, the T cells being the most affected. To gain insight into the mechanism(s) of the impairment displayed by these subjects, efforts have been centered on the study of in vitro cytokine production because of the pivotal role played by these mediators in the activation and control of several immune functions. The available results indicate that the ability to several immune functions. The available results indicate that the ability to produce interleukin-1 (IL-1), IL-2 and the soluble form of its receptor (sIL-2R) is impaired in HLA-B8,DR3 positive healthy subjects. To better characterize the cytokine production capacity of HLA-B8,DR3 positive subjects, we have investigated the pattern of in vitro production of IL-2, sIL-2R, IL-4. IL-6 and gamma-interferon (gamma-IFN) by mononuclear cells from HLA-B8, DR3 positive subjects after phytohaemoagglutinin stimulation. A significant decrease of IL-2, sIL-2R and gamma-IFN production by HLA-B8,DR3 positive subjects was observed. No significant difference was instead found between the HLA-B8,DR3 positive subjects and the negative ones as regards IL-4 and IL-6 production. We suggest that this imbalanced cytokine production may well account for the pattern of immune response that may observed in HLA-B8,DR3 positive subjects, i.e. a normal or increased humoral response in face of a low T cell immune responsiveness.

Adult↗

PubMed1994

Viral antibody titers are influenced by HLA-DR2 phenotype.

Antibody serum levels against herpes simplex type 1 virus, cytomegalovirus, viral capsid antigens of Epstein-Barr virus, and rubella virus were evaluated in a sample of the Sicilian population. Results demonstrated that HLA-DR2-positive individuals showed a significant increase in antibody titers, when compared to HLA-DR2-negative individuals. These observations seem to be in contrast with the reported association of the HLA-DR2 phenotype with an ineffective immune response against several infectious pathogens. On the other hand, an increased humoral response to viral antigens need not be interpreted as a marker for effective control of virus infections. In fact, the response to virus infections is related to the T-cell-mediated immune response restricted by class-I- or class-II-encoded proteins. Thus, the above-mentioned HLA-DR2-related susceptibility to certain viral infections could be associated with a preferential induction of an increased (although ineffective) antibody synthesis against viral antigens.

Adult↗

PubMed1993

The amino acid sequence of a protein from wheat kernel closely related to proteins involved in the mechanisms of plant defence.

The amino acid sequence of wheatwin1, a monomeric protein of 125 residues isolated from wheat kernel (variety S. Pastore), is reported. Wheatwin1 is highly homologous (95%) to barwin, a protein from barley seed, which was shown to be related to the C-terminal domain of two proteins encoded by the wound-induced genes win1 and win2 in potato and to a protein encoded by the same domain of the hevein gene (hev1) in rubber tree. Similarly to barwin, wheatwin1 contains six cysteine residues all linked in disulfide bridges and the N-terminal residue is pyroglutamate. Moreover, structural studies performed on wheatwin1 and win1 protein by predictive methods demonstrated that these proteins and barwin are closely related in the secondary structure also. The high level of homology found with the product of win1, win2, and hev1 genes strongly suggests that barwin and wheatwin1 play a common role in the mechanism of plant defence.

Amino Acid Sequence↗

PubMed1993

Natural killer and lymphokine-activated killer activity in HLA-B8,DR3-positive subjects.

The haplotype HLA-B8,DR3 is over-represented in several autoimmune diseases, implying that genes predisposing people to these disorders are linked to this haplotype. In these diseases, various dysfunctions reflecting an impairment of the immune system have been found. Several reports indicate also that in HLA-B8,DR3-positive healthy subjects similar disorders may be demonstrated. In the present work, we have evaluated NK and LAK activity in these subjects. The study has been performed on monocyte-depleted peripheral blood MNCs by using, the K-562 cell line as a target for NK activity and the HL-60 cell line for as a target LAK activity. LAK cells were obtained by incubating MNCs for 3 days with 100 U/ml of rIL-2. The results of our experiments demonstrate that NK cell activity is significantly decreased in healthy subjects bearing the HLA-B8,DR3 haplotype. Since the number of circulating CD16+ cells is not significantly different between HLA-B8,DR3-positive subjects and negative ones, it is unlikely that this defect is due to a decreased number of NK cells in effector cell preparations. The observation that the treatment with rIL-2 can restore the killer activity of MNCs from these subjects suggests instead that the reduced NK activity may be due at least in part to the imbalance of cytokine network that has been demonstrated in HLA-B8,DR3-positive subjects. Finally, since a decreased NK activity has been reported in the autoimmune diseases linked to this haplotype, our results support the suggestion that immunologic changes observed in autoimmune diseases reflect systemic regulatory disorders that have a genetic basis.

Adult↗

PubMed1993

Acetohydroxy acid synthase and threonine deaminase activities, and the biosynthesis of isoleucine-leucine-valine in Streptococcus bovis.

Acetohydroxy acid synthase (AHAS) and threonine deaminase (TD) activities were found in Streptococcus bovis and shown to be involved in the biosynthesis of the branched chain amino acids isoleucine, leucine and valine. Apparent lack of repression of AHAS synthesis by the end-products and reduced sensitivity of S. bovis growth to analogues of the branched chain amino acids suggested that secretion of isoleucine, leucine and valine in the growth medium may be a consequence of the regulatory features of AHAS. A glycyl-leucine-resistant mutant with reduced TD activity secreted a reduced amount of isoleucine and an increased amount of valine, which might be a result of the reduced rate of synthesis of the isoleucine precursor alpha-ketobutyrate and of a consequent preferential carbon flow through the valine branch of the pathway.

Acetolactate Synthase↗

PubMed1993

HLA-B8,DR3 phenotype and the antibody response against Epstein-Barr virus.

Antibodies against the viral capsid antigen (VCA) and nuclear antigens (EBNAs) of the Epstein-Barr virus (EBV) were determined in a sample of Sicilian population. A significant correlation was observed between HLA-B8,DR3 phenotype and reduced titres of antibodies to EBNAs, whereas HLA-B8,DR3 positive individuals displayed levels of antibodies to VCA comparable to those of HLA-B8,DR3 negative ones. These results further strengthen the suggestion that HLA-B8,DR3 positive subjects are low responders and that the depth of immune response depends on the fashion of antigenic challenge.

Adult↗

PubMed1993

gamma-Interferon, interleukin-4 and interleukin-6 in vitro production in old subjects.

It is well known that ageing is associated with various alterations of the lymphoid cell functions. Although both B and T cell are affected, the last appear to be more sensitive to ageing process. During the past years, to gain insight into thé mechanism(s) of this impairment, effort has been centered on the helper T cells specifically engaged in the production of interleukin-2 (IL-2) because of the pivotal role played by this cytokine in the activation of several immune functions. The results have demonstrated that the ability to produce IL-2 declines with age. In this paper we report the results of a study performed to determine the influence of age on the capacity to produce gamma-interferon (gamma-IFN), interleukin-4 (IL-4) and interleukin-6 (IL-6). Mononuclear cells from young and old subjects were assessed for cytokine producing capacity in response to phytohaemagglutinin stimulation. A significant decrease of gamma-IFN production by old subjects has been observed. No significant difference was instead observed between the old subjects and the young ones as regards IL-4 and IL-6 production. We suggest that this imbalanced cytokine production may well account for the pattern of immune response which may be observed in elderly, i.e. a normal or increased humoral response in face of a low T cell immune responsiveness.

Adult↗

PubMed1993

[The stress test in adolescents with and without a family history of arterial hypertension: the prognostic role of a systolic arterial pressure index].

A family history of hypertension can influence the behaviour of blood pressure during ergometric stress test (EST) in normotensive subjects, so that it is also used in the assessment of risk of hypertension. To evaluate the relationship between parental history and blood pressure values during exercise, 57 consecutive adolescents (aged 10-16 years) were studied. Out of them, 25 patients have not been considered because of the presence of organic pathologies of various nature that could interfere with the pressure behaviour. All patients underwent EST with a load increase of 25 W every 3 min until the maximal age-related heart rate. The patients were divided in 2 groups based on the presence (PH+ 13 patients, mean age 13 +/- 2 years) or on the absence (PH- 19 patients, mean age 13 +/- 2 years) of parental history of hypertension. No difference in body surface and maximum workload was observed between the 2 groups. Exercise test induced an increase in systolic blood pressure (SBP) both in PH- and PH+ patients, but no significant differences were found in any stage of the exercise in the 2 groups. Maximum heart rate (HR) was not different in the 2 groups and diastolic blood pressure (DBP) was substantially unchanged during exercise. The variation of SBP (delta SBP) between maximum stress and first, third, fifth and tenth min of the recovery phase were considered. Besides, 4 SBP indexes were deduced from the ratio of SBP values at the first, third, fifth and tenth min of the recovery by the SBP value at the acme of stress.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

[Effect of cilazapril therapy on diastolic filling and left ventricular hypertrophy in patients with arterial hypertension].

BACKGROUND: Of the main aspects of hypertension, left ventricular hypertrophy and appearance of cardiac dysfunction seem to be the most common and to produce an early and severe cardiac deterioration. Even in the presence of normal systolic function diastolic filling abnormalities are described. The efficacy of many antihypertensive drugs to decrease blood pressure and to reduce left ventricular hypertrophy has already been demonstrated. Cilazapril is a new ACE-inhibitor that in previous studies showed a very important antihypertensive effect. To assess its capacity, in long-term treatment, to reduce left ventricular hypertrophy we performed a prospective study on patients with mild hypertension. MATERIAL AND METHODS: Nineteen patients (aged 48 +/- 15 years) with mild hypertension (mean arterial pressure automatically recorded for 24 hours with blood pressure ambulatorial monitoring) were treated with cilazapril (5 mg/day) for 1 year. Doppler echocardiography was performed: at the beginning, after 6 months and after one year of therapy. The following parameters were evaluated: interventricular septal and posterior wall thickness, LV end-diastolic diameter, LV mass index, early (E) and late (A) diastolic filling flow velocities and the ratio E/A. RESULTS: A significant decrease was observed in mean arterial pressure (from 130 +/- 14 mmHg at beginning to 102 +/- 11 mmHg at six months of therapy and to 103 +/- 9 mmHg at one year of therapy). A significant reduction in LV hypertrophy and an improved diastolic filling pattern of the left ventricle was shown after six months of therapy with cilazapril; this improvement still remained after 1 year of therapy. CONCLUSIONS: In this study antihypertensive efficacy of cilazapril has been confirmed. Moreover, in long treatment, cilazapril has been useful to reduce left ventricular hypertrophy and to improve diastolic filling without significant side effects.

Adolescent↗

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↗