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R Santacroce

Publications and source records attributed to R Santacroce.

10 recordsLinked to original sources
PubMed2006

Low protein Z levels and risk of occurrence of deep vein thrombosis.

BACKGROUND: Protein Z (PZ) serves as a cofactor for activated factor X inhibition by the PZ-dependent protease inhibitor. In vivo and in vitro studies aimed at investigating the role of PZ levels in venous thombosis have produced conflicting results. OBJECTIVES: We investigated whether reduced PZ levels and PZ gene common variants are associated deep vein thrombosis (DVT). PATIENTS AND METHODS: In 197 patients with DVT and in 197 age-matched and sex-matched controls, PZ plasma levels and gene polymorphisms were evaluated by means of an enzyme-linked immunosorbent assay and direct cycle sequence analysis. RESULTS: Similar PZ levels were found in controls (1.44; SD 0.63 microg mL-1) and in patients (1.44; SD 0.96 microg mL-1). The incidence of PZ levels below the 5.0 (0.52 microg mL-1) or the 2.5 percentile of controls (0.47 microg mL-1) was higher in patients (10.2% and 8.7%, respectively) than in controls {4.1% [odds ratio (OR) 2.7, 95% confidence interval (CI) 1.2-7.3], and 2.0% (OR 4.6, 95% CI 1.5-13.9), respectively}. This relationship was independent of the effect of age, sex, and factor V Leiden and FII A(20210) alleles [OR 2.8 (95% CI 1.1-7.3), and OR 4.9 (95% CI 1.4-17.3)]. PZ levels were associated with the intron C G-42A and the intron F G79A polymorphisms in cases (r2=0.129) and in controls (r2=0.140). However, frequencies of the PZ gene polymorphisms were similar in the two groups and were not associated with very low PZ levels. CONCLUSIONS: The present data suggest an association between very low PZ plasma levels and the occurrence of DVT, with PZ gene polymorphisms contributing little to this relationship.

Adult↗
PubMed2006

Identification of fetal gender in maternal blood is a helpful tool in the prenatal diagnosis of haemophilia.

Fetal DNA identification in maternal circulation has provided a new approach for non-invasive prenatal diagnosis. However, fetal DNA can persist in maternal blood long after the delivery, severely hampering this possibility. We addressed the issue of fetal DNA persistence in maternal blood. Thus, we investigated cell-free fetal DNA as a reliable approach in prenatal diagnosis of haemophilia. Forty non-pregnant women, who had had at least a male fetus, 29 control pregnant women, and 14 pregnant women, carriers of hemophilia A or B. The assessment of Y-chromosomal sequences was performed by analysing SRY and amelogenin genes using PCR-based techniques. A protocol consisting of double centrifugation at full speed followed by plasma filtration hampered the detection of Y chromosome-specific sequence in non-pregnant women. In 29 control pregnant women, blinded determination of fetal sex confirmed the specificity and sensitivity of the method applied. In 14 pregnant carriers of hemophilia, the investigation revealed a male fetus in nine pregnancies. Excluding the three cases in which a spontaneous miscarriage occurred, the sensitivity and specificity of fetal sex prediction by SRY and amelogenin gene analyses were both 100% as compared with the invasive approach and the fetal sex outcome at birth (six males and five females). Because of its high accuracy in prediction, fetal gender determination with cell-free fetal DNA in maternal plasma may be a useful tool in prenatal diagnosis of haemophilia allowing for the avoidance of invasive procedures for female fetuses.

Adult↗
PubMed2001

A comprehensive on-line digestion-liquid chromatography/mass spectrometry/collision-induced dissociation mass spectrometry approach for the characterization of human fibrinogen.

An automatic on-line digestion-liquid chromatography/mass spectrometry/collision-induced dissociation mass spectrometry (LC-MS/CID-MS) protocol has been developed for detection of errors in the biosynthesis of human fibrinogen, such as amino acid (AA) mismatch or incorrect post-translational modification (PTM). Using on-line digestion on an immobilized-enzyme column, the reaction time is significantly reduced (less than 20 min) and the entire approach is suitable for automation. The two-loop MS experiments (full-scan acquisition and sugar moieties monitoring by SIM) allow checking both the correct AA mapping via the peptides generated by the digestion of the PTM. Since the protocol was designed for application on a routine basis, as a proof-of-concept detection of a rare case of 'abnormal' fibrinogen has been demonstrated. The advantage of the proposed approach is exemplified by the fact that the DNA sequence information for the case investigated had not shown any evidence of the abnormality.

Chromatography, Liquid↗
PubMed2001

Nicotine effects on polymorphonuclear cell apoptosis and lipopolysaccharide-induced monocyte functions. A possible role in periodontal disease?

Apoptosis provides a mechanism for clearance of unwanted cells in a variety of situations in which programmed or physiological cell death occurs; but the premature death of defensive cells could promote infection, inflammation and concomitant disease. We detected high values of apoptosis in polymorphonuclear cells (PMN) elicited from crevicular sulci of smokers affected by adult periodontitis. To learn more about the effects of nicotine on the periodontal environment, we studied its ability to modulate the apoptosis of two phagocytic lines, PMN and mononuclear cells, which are continuously recruited from gingival vessels to prevent or control plaque extension. Brief exposure of PMN to nicotine concentrations ranging from 0.01 to 0.3% shortened, in a dose-dependent relationship, the lag culture time required to observe at fluorescent microscopy the morphological traces of apoptosis. These observations were confirmed by specific tools of apoptosis: DNA fragmentation on gel electrophoresis and expression of the apoptosis-signaling receptor Fas/Apo-1. The apoptotic effect excited by nicotine on these first line defensive cells may be an important feature of the pathogenesis of periodontal disease. As for mononuclear leukocytes, nicotine was unable to induce apoptotic modifications on cells observed up to 72 h culture time, but the drug inhibited IL-1beta release and procoagulant activity (PCA) expression. The conflicting role played by these lipopolysaccharide (LPS)-induced monocyte functions in the inflammatory process is a further intrigue in the mechanism by which nicotine compromises the oral health.

Apoptosis↗
PubMed2001

A frameshift mutation in the human fibrinogen Aalpha-chain gene (Aalpha(499)Ala frameshift stop) leading to dysfibrinogen San Giovanni Rotondo.

We have investigated a 53-yr-old asymptomatic white man with decreased functional, but not immunologic, fibrinogen plasma levels together with prolonged thrombin and reptilase times, detected through routine coagulation studies prior to a surgical procedure. A new heterozygous single nucleotide deletion (C) at position Ala499 within the Aalpha-chain gene was identified, which predicted changes of the corresponding amino acids encoded by the subsequent portion of the exon V and the appearance of a premature stop codon at position 518 (Aalpha[499]Ala frameshift stop). The new dysfunctional fibrinogen, San Giovanni Rotondo variant, was confirmed in vivo by SDS-PAGE analysis of HPLC-purified fibrinogen chains. Mass spectrum examination of the abnormal HPLC-purified peak gave an estimated mass (56,088 Da) similar to that predicted by DNA analysis of the mutated Aalpha-chain gene (56,088 Da) and, after tryptic digestion, the truncated Aalpha-chain was shown only in the propositus, who also carried normal Aalpha-chain. In addition, mass spectrum analysis of the tryptic digest of the abnormal chain confirmed the presence of a new and unpaired cysteine at the last position that was predicted to form a disulfide bridge with human serum albumin. Immuno-blot analysis confirmed that fibrinogen San Giovanni Rotondo variant, but not normal fibrinogen. contained substantial amounts of albumin. Present findings confirm that truncated Aalpha-chain lacking part of the terminal domain may be incorporated into mature fibrinogen molecules and normally secreted in the bloodstream.

Afibrinogenemia↗
PubMed2000

A G-to-A mutation in IVS-3 of the human gamma fibrinogen gene causing afibrinogenemia due to abnormal RNA splicing.

Congenital afibrinogenemia is a rare autosomal recessive disorder characterized by a hemorrhagic diathesis of variable severity. Although more than 100 families with this disorder have been described, genetic defects have been characterized in few cases. An investigation of a young propositus, offspring of a consanguineous marriage, with undetectable levels of functional and quantitative fibrinogen, was conducted. Sequence analysis of the fibrinogen genes showed a homozygous G-to-A mutation at the fifth nucleotide (nt 2395) of the third intervening sequence (IVS) of the gamma-chain gene. Her first-degree relatives, who had approximately half the normal fibrinogen values and showed concordance between functional and immunologic levels, were heterozygtes. The G-to-A change predicts the disappearance of a donor splice site. After transfection with a construct, containing either the wild-type or the mutated sequence, cells with the mutant construct showed an aberrant messenger RNA (mRNA), consistent with skipping of exon 3, but not the expected mRNA. Sequencing of the abnormal mRNA showed the complete absence of exon 3. Skipping of exon 3 predicts the deletion of amino acid sequence from residue 16 to residue 75 and shifting of reading frame at amino acid 76 with a premature stop codon within exon 4 at position 77. Thus, the truncated gamma-chain gene product would not interact with other chains to form the mature fibrinogen molecule. The current findings show that mutations within highly conserved IVS regions of fibrinogen genes could affect the efficiency of normal splicing, giving rise to congenital afibrinogenemia.

Afibrinogenemia↗
PubMed2000

Simple two-color array-based approach for mutation detection.

The ability to analyze multiple polymorphic/mutation sites rapidly and accurately is pivotal in all areas of genetic analysis. We have applied single nucleotide primer extension (SNE) for detection of multiple point mutations in a micro-array format using two-color, fluorescent dye-tagged dideoxynucleoside triphosphate terminators (ddNTPs). The oligonucleotide primer ending one nucleotide short of the mutation site being probed is bound to the slide and single-base extended in place with two different Cy5/Cy3 dye-tagged terminators using solution-phase, locus-specific, single-stranded complementary templates generated by PCR from genomic DNA. The composite fluorescence produced contains peaks of distinct wave lengths corresponding to each Cy dye-tagged terminator incorporated, resulting in a fluorescent 'fingerprint' for each DNA target. DNA polymerase-catalyzed incorporation of Cy dye-tagged dideoxynucleoside triphosphates was dependent on the particular dyes, the specific ddNTP, the DNA target concentration, sequence of the template, on-slide temperature cycling and washing conditions. Results from analysis of mutations in the human hemochromatosis and connexin 26 genes show that this approach has several advantages over existing methods and is simple, rapid, robust, cost effective and accurate with potential applications in many areas of genetic analysis.

Amino Acid Substitution↗
PubMed1998

Sulfide enhancement of PMN apoptosis.

Hydrogen sulfide is a toxic metabolite released by several bacterial agents under anaerobic conditions. In the present paper, we investigated the effects of sulfide on polymorphonuclear cell (PMN) apoptosis, a mechanism suggested for limiting the toxic potential of neutrophils in inflammatory sites. We showed that 1 mM sulfide (concentration not conditioning PMN viability) is able to enhance the apoptotic fate of human granulocytes by increasing: i) the number of cells containing pyknotic nuclei, ii) the internucleosomal cleavage, and, iii) the intensity of tubulin immunofluorescence staining. The sulfide effect is partially prevented by ionomycin and this finding is consistent with the hypothesis of the inhibiting role played by high levels of cytosolic calcium in PMN apoptosis modulating.

Apoptosis↗