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Biomedical subjects

G Valentini

Publications and source records attributed to G Valentini.

At least 181 records · Page 10Linked to original sources
PubMedDate not supplied

Dehydroepiandrosterone sulphate serum levels in systemic sclerosis.

OBJECTIVE: To evaluate in a cohort of women with systemic sclerosis (SSc) the dehydroepiandrosterone sulphate (DHEAS) serum levels and their relationship with disease severity. METHODS: DHEAS serum concentrations were measured by radioimmunoassay in 40 SSc patients and compared with those in 40 controls matched for sex and reproductive status. IL-2 sR alpha was evaluated as a disease activity index. A preliminary organ/system severity scale proposed by Medsger et al. in 1999 was used to evaluate disease severity. RESULTS: Mean serum levels of DHEAS in SSc women of childbearing age were significantly lower than in controls (0.87 +/- 0.85 microgram/ml versus 2.75 +/- 0.42 micrograms/ml; p < 0.001). On the contrary, no difference was found between postmenopausal women and controls. A reduction below the 95% confidence limits was found in 10 out of 11 patients of childbearing age and in 8 out of 29 postmenopausal women, respectively. In 5 out of 11 patients of childbearing age taking steroids for their SSc (< 10 mg/daily) DHEAS levels were significantly lower than in patients not taking steroids (p = 0.01). On the contrary, 16 out of 29 postmenopausal women using steroids had lower DHEAS concentrations than in patients not taking steroids, although the difference was not statistically significant. There was no statistically significant difference in DHEAS levels between patients with diffuse or limited SSc, or between those with or without organ system involvement. No correlations were found either in pre- and post-menopausal steroid nonusers, or in limited and diffuse subsets, between DHEAS levels and age, postmenopausal years, disease duration, IL-2 sR alpha, disease organ/system severity scale. CONCLUSION: Our data show that, as in other autoimmune diseases, low serum DHEAS is a feature of premenopausal SSc patients. More extensive prospective studies are needed to define the exact role of DHEAS dysregulation in SSc.

Adolescent↗
PubMedDate not supplied

Immunohistologic markers of immune activation and changes of glycosylation of serum proteins in primary Sjögren's syndrome.

OBJECTIVE: [corrected] To assess the possible correlations between the immune activation of certain surface antigens at the lip salivary gland (LSG) level, and changes in glycosylation of serum proteins in primary Sjögren's syndrome (SS). METHODS: LSG biopsy samples were obtained from 22 SS patients (mean age 56.3 years; mean disease duration 70.8 months) and prepared for immunohistochemical analysis using murine monoclonal antibodies for interleukin-2 receptor (IL-2R) (CD25) and for the class II major histocompatibility antigen HLA-DR. The glycosylation of serum proteins was evaluated in all patients by an enzyme-linked lectin assay (ELLA) using concanavalin A (Con A). RESULTS: In LSG specimens the presence of IL-2R was observed at the infiltrating level, mainly periductally, in 13 (59%) cases and on the epithelial cells of 14 (64%) patients. In 13 out of 22 SS patients (59%) a marked positivity both of the infiltrates and of the epithelium was found for anti-HLA-DR monoclonal antibody. The degree of expression of different antigens on LSG samples was correlated with their histologic class according to Tarpley evaluation. The positivity for IL-2R and HLA-DR molecules on glandular tissues was correlated. A significant increase in the total Con A reactivity of serum proteins was found in those patients expressing IL-2R and HLA-DR antigens on LSG specimens. CONCLUSIONS: The co-expression of IL-2R and HLA-DR antigens on both the epithelium and infiltrates of LSG is consistent with a participation of these cells in the immune process of SS. Moreover, changes in the glycosylation of serum proteins seem to be related to the presence of these immunoactivation markers of the disease at the LSG level, suggesting that the control of protein glycosylation could be mediated by the same mechanisms involved in the tissue damage of SS.

Adult↗
PubMedDate not supplied

Vesical telangiectasias as a cause of macroscopic hematuria in systemic sclerosis.

A 36-year-old female with diffuse cutaneous systemic sclerosis (dcSSc) developed macrohematuria due to vesical telangiectasias that was responsive to diathermocoagulation of the vasal lesions. This is the first report of a patient with dcSSc and vesical telangiectasias leading to severe macrohematuria that was successfully treated with diathermocoagulation.

Adult↗
PubMedDate not supplied

Isolated autoimmune response: definition, analysis of the prevalence in an outpatient rheumatology clinic, relationship to pre-clinical autoimmune disease and infections by hepatotropic viruses.

OBJECTIVE: To define the clinical significance of non-organ specific autoantibody positivity in patients in whom routine clinical and laboratory examinations did not detect any disease that might have caused the serological finding. METHODS: Out of 1,120 patients consecutively admitted to an outpatient rheumatology clinic, 28 were referred for the evaluation of an autoantibody positivity unrelated to the clinical status. These patients and 28 sex- and age-matched controls underwent a specific work-up with the aim of detecting any underlying infection or autoimmune disease. RESULTS: Eight of the 28 patients (28.5%) were found to be affected by a previously undetected disease: 3 chronic hepatitis C, 3 Sjögren's syndrome, and 2 autoimmune thyroiditis. The remaining 20 did not show any autoimmune or hepatic disease, although 4 of them showed active infection by HBV (n = 1) or HGV (n = 3) and 15 had had a previous infection by hepatotropic viruses (HBV, CMV or EBV). After a follow-up lasting 6-54 months, none of the last 20 patients developed any autoimmune or chronic hepatic disease. CONCLUSIONS: A diagnostic work-up is necessary in patients presenting with unexpected autoantibody positivity in order to detect an underlying pre-clinical autoimmune disease and/or unexpected hepatic infection. Patients in whom such a work-up fails to point out any condition should be further followed in order to make an early diagnosis of autoimmune disease.

Adolescent↗
PubMedDate not supplied

Fructose 1,6-bisphosphate-activated pyruvate kinase from E. coli: ligand promoted conformational changes.

The ligand-dependent susceptibility to heat inactivation and to tryptic digestion and the intrinsic fluorescence of the fructose 1,6-bisphosphate-activated pyruvate kinase from Escherichia coli were investigated in the absence and in the presence of physiological ligands. With respect to the enzyme alone, binding of the allosteric activator fructose 1,6-bisphosphate makes the protein sensitive to tryptic attack and thermolabile, while binding of phosphoenolpyruvate and Mg2+, but not of either ligand separately, induces in the enzyme a highly thermostable conformation, the attainment of which does not require an ordered binding sequence of the two ligands. The apparent loosening of the enzyme structure induced by fructose bisphosphate suggests that the activation it exerts at low phosphoenolpyruvate concentration might be due to an increased accessibility of substrate to the active site.

Binding Sites↗
PubMedDate not supplied

Bioactivity of prolactin in systemic sclerosis.

OBJECTIVES: To evaluate basal serum prolactin (PRL) levels in systemic sclerosis (SSc) patients with different degrees of skin involvement, and investigate its relationship with some of the clinical and serological parameters of the disease. METHODS: Basal serum PRL was measured in 44 SSc patients (38 F, 6 M) using a rat NB2 lymphoma line cell proliferation assay. Other parameters measured were: serum aminoterminal propeptide of type III procollagen (PIIINP) by RIA; soluble alpha interleukin-2 receptor (IL-2 sRalpha), serum intercellular adhesion molecule-1 (ICAM-1), von Willebrand factor (vWF) by ELISA; the erythrocyte sedimentation rate (ESR); and C-reactive protein (CRP). Skin and organ/system involvement were assessed according to Medsger et al.'s organ/system severity scale, and global disease activity index according to Valentini et al. RESULTS: The serum PRL concentration in the SSc patients was 13.8 ng/ml (95%CI from 3.2 to 49.1 ng/ml), similar than that in control subjects (12.8 ng/nl: 95%CI 3.0 to 18.4 ng/ml). Hyperprolactinemia, defined as a level > 20 ng/ml (mean 30.9 ng/ml, median 29.3) was found in a total of 6 cases (13.6%; 95%CI 5.8 to 28%) cases: in 1 out of 6 men (16.7%; 95%CI -26% to 59%) and similarly in 5/38 women (13.2%; 95%CI 1.9% to 24.4%). No correlation was found between PRL levels and SSc subgroup (lcSSc, icSSc, dcSSc), serologial parameters, or the level of disease activity. Finally, no significant correlations were found with clinical or serological variables. CONCLUSIONS: The findings confirm that mild hyperprolactinemia occurs in at subgroup of SSc patients. However, prospective studies are needed to better define the relationship between PRL and disease activity in scleroderma.

Adolescent↗
PubMedDate not supplied

Hashimoto's thyroiditis is associated with peripheral lymphocyte activation in patients with systemic sclerosis.

OBJECTIVE: To investigate whether autoimmune thyroiditis [HT] (i.e., a TH1 disease) influences the pattern of peripheral lymphocyte activation in systemic sclerosis [SSc] (commonly regarded as a TH2 disease). Twenty SSc patients, 6 with (SSc+HT+) and 14 without HT (SSc+HT-) and 20 controls were investigated for the intracellular content of IFN-gamma and IL-4 in unstimulated and stimulated (25 ng/ml PMA and 1 microg/ml ionomycin) CD4+ and CD8+ T lymphocytes. Results Under basal conditions the percentages of CD4+IFN-gamma, CD4+IL-4+ and CD8+IFN-gammawere significantly higher in the patients than the control subjects, no significant differences being detectable between the two patient subgroups. Upon PMA stimulation, the 20 SSc patients showed a higher percentage of CD4+IFN-gamma+ and CD8+IFN-gamma+ than the control subjects. In particular, the 14 SSc+HT- patients showed a higher number of CD4+IFN-y+ and CD4+IL-4+ cells, while the SSc+HT+ patients showed higher percentage of CD8+IFN-gamma+ cells. The latter patients showed a reduced percentage of CD4+IL-4+ cells and an increased percentage of CD8+IFN-y+ in comparison with the SSc+HT- patients. Type-1 activation in the peripheral blood of SSc patients has been already pointed out by other authors and ourselves. This study shows that such activation mainly affects SSc patients with coexistent HT.

Adolescent↗
PubMedDate not supplied

Localized and systemic forms of scleroderma in adults and children .

Systemic sclerosis (SSc) presents a great deal of variability in the extent and severity of skin and internal organ involvement. The diagnostic and prognostic significance of autoantibodies in SSc is undisputed and the patient's autoantibody profile represents a fundamental tool for clinicians. Scleroderma is a rare condition in children. Unlike adults, localized scleroderma is more frequent than the systemic sclerosis, nevertheless it represents a disabling condition. In both conditions, no validated outcome measures and proven effective treatment is available to date.Raynaud's phenomenon (RP) is one the most common and significant clinical symptoms of SSc and therefore in patients with RP a capillaroscopic analysis should be carried out as soon as possible. The actual and select advantage of the early nailfold videocapillaroscopic (NVC) analysis is to distinguish between the primary RP and the secondary RP and to allow the early detection of SSc.

Adult↗
PubMedDate not supplied

[Thrombocytosis in progressive generalized sclerosis (scleroderma) and in other rheumatic diseases].

A platelet count was made in 37 patients with Progressive Systemic Sclerosis (PSS), 6 with Sjögren's Syndrome, 11 with Rheumatic Polymyalgia with or without Horton's Arteritis (PMR-AH), 26 with Ankylosing Spondylitis (A.Sp.), 29 with Psoriatic Arthritis, 15 with Gout and in 65 healthy subjects. In this last group the mean platelet count was 215.692/mm3, S.E. 4.167. In the various groups of patients the following mean platelet counts were determined: PSS 242.108 +/- 11.766; Sjögren 245.000 +/- 22.620; PMR-AH 276.818 +/- 25.577; A.Sp. 272.846 +/- 14.124; Psoriatic Arthritis 245.833 +/- 9.374; Gout 265.333 +/- 24.628. Statistical analysis showed a significant difference (P less than 0.05), (P less than 0.01) or (P less than 0.001) between each group of patients and the controls. However, the platelet count in the majority of patients in each group was not higher than 300.000/mm3. Statistically significant correlations were found between platelet count and some biolgoical inflammation parameters. All patients with platelets higher than 300.000/mm3 showed a high disease activity. Yet some patients with marked inflammation did not present thrombocytosis. According to literature data thrombocytosis in Rheumatoid Arthritis is considered to be correlated to disease activity. The results of this study indicate that even in other rheumatic diseases thrombocytosis is often present, apparently correlated to the inflammation. Therefore thrombocytosis is an inflammation parameter; but it is less sensitive than other ones.

Adult↗
PubMedDate not supplied

Serum beta 2-microglobulin in patients with monoclonal gammopathies.

Beta-2-microglobulin concentrations were determined in serum samples from 45 patients with benign and malignant monoclonal gammopathies. In the group of patients suffering from multiple myeloma or Waldenström macroglobulinemia the mean beta 2-microglobulin level was significantly higher than in the group with monoclonal gammopathy of undetermined significance. Values above 3 mg/L were highly indicative of a neoplastic process and were observed in all the Waldenström patients and in greater than 90% of myeloma patients. No significant correlation was noticed between beta 2-microglobulin and monoclonal protein levels in any of the groups examined.

Adult↗
PubMedDate not supplied

[Sjogren-Larsson syndrome. Description of a case].

The authors describe a typical case of Sjogren-Larsson Syndrome showing a clear improvement of the spastic paresis after 2 years of physiotherapy and a diet rich in polyunsaturated fatty acids.

Fatty Acids, Unsaturated↗
PubMedDate not supplied

A simple procedure for the purification of neutral salt soluble type I collagen from skin.

Intact monomeric type I collagen was purified from fetal bovine skin by a simple and time saving procedure. Saline precipitates of mixed skin collagens, in 4 M NaCl, were extracted with a limited volume of dilute acetic acid, taken in the proportion of 1 ml per g of original wet skin; NaCl in the precipitate was not removed by dialysis. The salt concentration in the extraction medium in the above conditions, selectively solubilized type I collagen.

Acetates↗
PubMedDate not supplied

Monovalent cations requirement of the fructose 1,6-bisphosphate-activated pyruvate kinase from E. coli.

The fructose 1,6-bisphosphate-activated pyruvate kinase from Escherichia coli has been purified by a simplified procedure, which gives a homogeneous enzyme in approximately half the working time required by other methods and is suitable for large scale preparations. The activity of the enzyme is strictly dependent on the presence of monovalent cations. Enzyme activity is elicited by K+ and NH4+, but not by Na+. Homotropic cooperativity is displayed in the activation by K+ and NH4+ and heterotropic effects are reciprocally exerted by monovalent cations and other ligands, such as phosphoenolpyruvate and fructose 1,6-bisphosphate. The allosteric nature of such interactions is suggested by changes in heat stability of the enzyme induced by K+ and fructose 1,6-bisphosphate. NH4+, but not K+, at high concentrations, cause an inhibition of enzyme activity.

Cations, Monovalent↗