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C Tassi

Publications and source records attributed to C Tassi.

At least 19 recordsLinked to original sources
PubMed2006

Early detection of insulin deprivation in continuous subcutaneous insulin infusion-treated patients with type 1 diabetes.

BACKGROUND: This study was performed to define the clinical relevance of early changes of capillary 3beta-hydroxybutyrate (3betaOHB), for detection of metabolic deterioration before occurrence of overt diabetic ketoacidosis following interruption of continuous subcutaneous insulin infusion (CSII). METHODS: An open clinical trial was performed with eight patients with type 1 diabetes on CSII therapy. After an overnight fast, at 8 a.m. (T0) CSII was interrupted for 4 h. At noon (T240) CSII was re-established, and at 4 p.m. (T480) the study was ended. Blood glucose (BG) and capillary and plasma 3betaOHB were measured at 30-min intervals, plasma insulin at 60-min intervals, and urinary ketones at 120-min intervals. RESULTS: After CSII interruption mean BG increased from 149.8+/-54.4 mg/dL at T0 to 224.8+/-56.2 mg/dL at T240 (P<0.05), and mean capillary 3betaOHB increased from 0.1+/-0.1 mmol/L at T0 to 0.9+/-0.6 mmol/L at T240 (P<0.001). The rate of increase of capillary 3betaOHB was faster and significantly more relevant than that of BG (P<0.05). The restoration of CSII produced a significant reduction of mean BG and capillary 3betaOHB (T480, 119.5+/-24 mg/dL and 0.2+/-0.2 mmol/L, respectively; P<0.05 for both vs. T240). The recovery of capillary 3betaOHB was significantly faster than that of BG (P=0.03). CONCLUSIONS: The dynamic evaluation of changes of capillary 3betaOHB levels can represent a useful support to home BG monitoring in the event of CSII interruption, providing faster information on early metabolic deterioration due to insulin deprivation and allowing preventative action for avoiding the evolution towards overt diabetic ketoacidosis. After reintroduction of insulin infusion the monitoring of the faster recovery of 3betaOHB relative to BG can provide useful information for the prevention of late hypoglycemia due to insulin overinfusion.

3-Hydroxybutyric Acid↗
PubMed2005

Antiapoptotic role of p38 mitogen activated protein kinase in Jurkat T cells and normal human T lymphocytes treated with 8-methoxypsoralen and ultraviolet-A radiation.

A combination of 8-methoxypsoralen and ultraviolet-A radiation (320-400 nm) (PUVA) is used for the treatment of T cell-mediated disorders, including chronic graft-versus-host disease, autoimmune disorders, and cutaneous T-cell lymphomas. The mechanisms of action of this therapy, referred to as extracorporeal phototherapy, have not been fully elucidated. PUVA is known to induce apoptosis in T lymphocytes collected by apheresis, however no information is available concerning the underlying signaling pathways which are activated by PUVA. In this study, we found that PUVA treatment of Jurkat cells and human T lymphocytes up-regulates the p38 MAPK pathway but not the p42/44 MAPK or the SAPK/JNK signaling networks. The use of a pharmacological inhibitor selective for the p38 MAPK pathway, SB203580, allowed us to demonstrate that this network exerts an antiapoptotic effect in PUVA-treated Jurkat cells and T lymphocytes from healthy donors. Moreover, the effect of SB203580 was not due to a down-regulation of the Akt survival pathway which was not activated in response to PUVA. These results may suggest that p38 MAPK-dependent signaling is very important for the regulation of survival genes after exposure to PUVA. Since the therapeutic effect of PUVA seems to depend, at least in part, on apoptosis, further studies on the apoptosis signaling networks activated by this treatment might lead to the use of signal transduction modulators in combination with PUVA, to increase the efficacy of this form of therapy.

Apoptosis↗
PubMed2005

Short- and long-term haematological surveillance of healthy donors of allogeneic peripheral haematopoietic progenitors mobilized with G-CSF: a single institution prospective study.

Healthy allogeneic donors, who were treated with G-CSF and underwent peripheral blood haematopoietic precursor collection at our Institution, were enrolled in a short- and long-term haematological surveillance protocol for a 5--7--year period. To date, 94 donors have been assessed with a mean follow-up of 30 months (4--84); for 30 subjects, the follow-up is >or=48 months. During G-CSF administration, 23/94 donors showed a significant platelet count decrease from the baseline. Pre-apheresis platelet decrement correlated with the total G-CSF dose administered, baseline platelet level and donor age. Normal platelet counts returned within 4--8 months. PMN and/or lymphocyte lower values were observed in 55/94 donors 2 weeks after G-CSF administration, with mean drops from the baseline of 40 and 36% for PMN and lymphocytes, respectively. The PMN decrease correlated inversely with donor age, as younger donors were more affected than older ones, whereas the lymphocyte decrease correlated directly with the total blood volumes processed in the apheresis courses, in particular for donors subjected to large volume leukaphereses. Long-term observation showed moderate neutrophil reduction (25% count drop from the baseline) in four of the 30 donors observed for four years or more. 14 donors showed persistent, slight lymphocytopenia (mean drop of 13%) until the third year, with recovery in the fourth year of follow-up.

Adult↗
PubMed2004

Expression modes of urinary N-acetyl-beta-D-glucosaminidase in patients with chronic renal insufficiency.

BACKGROUND: Urinary N-acetyl-beta-D-glucosaminidase (NAG) activity has emerged as potentially useful early marker of renal tubular injury. This activity is usually evaluated in random urine samples and is related to urinary creatinine concentration. Reports about the lack of correlation between NAG activity of 24-h urines and activity of random urine samples in some clinical and experimental situations led us to study the correlation existing between different procedures for expressing urinary NAG in patients with chronic renal insufficiency. METHODS: Thirty samples of 24-h urine and 30 random urine samples from chronic renal insufficiency patients were collected. The activity of urinary NAG was examined fluorimetrically. RESULTS: The following correlations were observed: (1) r = 0.431 (P = 0.017) for activity in random urine samples and total activity in 24-h urines); (2) r = 0.281 (P = 0.005) for activity in random samples and activity, expressed as U/l, in 24-h urines. CONCLUSIONS: The data show that collection of urine excreted over the whole day and evaluation of total daily excretion of NAG seems the method of choice, at least for patients with chronic renal insufficiency.

Acetylglucosaminidase↗
PubMed2004

N-acetyl-beta-D-glucosaminidase activity in urine of dental personnel.

BACKGROUND: Dental personnel is exposed to several potential nephrotoxic agents. Urinary N-acetyl-beta-d-glucosaminidase (U-NAG) activity has emerged as a sensitive marker of early nephrotoxicity. METHODS: U-NAG was evaluated, by fluorimetric assay, in urine from 30 healthy subjects and 30 dental personnels. RESULTS: The median value of U-NAG activity (133.5 U/mmol urinary creatinine (U-Cr) in urines of dental personnel was not statistically different (P>0.05) from activity (100.7 U/mmol U-Cr) of control urines. CONCLUSIONS: The results suggest that, for dental personnel, exposure to potential nephrotoxic agents is not usually high enough to increase U-NAG activity.

Acetylglucosaminidase↗
PubMed2003

Flow cytometry characterization of white cell-reduced blood: apoptosis markers and morphology of postfiltration elements.

BACKGROUND AND OBJECTIVES: Apoptosis affects white blood cells (WBCs) contained in packed red blood cell (RBC) units. This phenomenon was recently described also in residual WBCs after filtration. The aim of this study was to better characterize the residual WBCs postfiltration by using apoptosis markers and morphology. MATERIALS AND METHODS: Immunofluorescence, flow cytometry and cell-sorting techniques were utilized. RESULTS: Residual leucocytes of leucodepleted packed RBC units showed increasing values of apoptotic elements in a time-course experiment. We also demonstrated that these elements are positive for APO 2.7 monoclonal antibody (mAb), poly ADP-ribose polymerase (PARP) cleavage and fluorescein isothiocyanate (FITC)-conjugated N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK), all of which indicate that programmed death is a feature of this population of cells. Phenotypic analysis with CD45 side-scatter gating demonstrated also that CD15 and CD16 granulocyte-associated antigens are present on a subset of postfiltration leucocytes. Moreover, the expression of human leucocyte antigen (HLA) class I antigens is maintained. Sorting of CD45-positive cells and morphological analysis of these samples confirmed that leucocytes in postfiltration units have morphological characteristics of dying cells. CONCLUSIONS: Our study extends previous observations regarding the morphology and function of apoptotic cells in leucodepleted blood units, which suggested the presence of apoptotic cells in postfiltration leucocytes. Cleaved PARP, APO 2.7 mAb and positivity for the FITC-conjugated Z-VAD-analogous reagent strongly suggest the activation of programmed death pathways. In addition, the maintained granulocyte-associated and HLA class I antigens might recall an immune response in multitransfused patients.

Apoptosis↗
PubMed2002

Apoptosis in leucodepleted packed red blood cells.

BACKGROUND AND OBJECTIVES: Packed red blood cells (pRBCs) contain apoptotic white cells. We studied apoptotic cells in pRBCs after filtration and at various time-points during storage. MATERIALS AND METHODS: To maintain the same subset of cells, seven pRBC units were pooled in a single bag and divided equally into seven aliquots. Two series of five experiments were performed: in the first we utilized the Biofil R01 Max filter, and in the second the Pall BPF4 filter was used. One aliquot was immediately leucodepleted while the others were stored at 4 degrees C and filtered on days 3, 7, 10, 14, 21 and 42 of storage. The postfiltration leucocyte counts and apoptotic evaluations were performed by using the Nageotte chamber and flow cytometry. RESULTS: The absolute number of residual leucocytes was always less than 0.5 x 106 in each experiment. Nageotte chamber counts showed a greater number of white blood cells than flow cytometry during the 42 days of storage. On day 0, the percentage of apoptotic cells in non-leucodepleted pRBCs was 1.1 +/- 0.4 and 1.2 +/- 0.4, while in filtered pRBCs it was high from day 0, at 53.5 +/- 16.3 and 52 +/- 18.5, respectively, with Biofil and Pall filters. On day 10 of storage, apoptotic cells reached a percentage of 42.5 +/- 15.8 and 41.6 +/- 18.6 in non-leucodepleted pRBCs, while in filtered units an average value of approximately 90% was found with both filters. CONCLUSIONS: The percentage of apoptotic cells was higher in leucodepleted than in non-leucodepleted pRBCs. After filtration, the degree of apoptosis was already high on day 0, and reached a mean of approximately 90% by day 10. The difference in residual WBC counts between the Nageotte chamber and flow cytometry could be related to the presence of a high percentage of apoptotic cells in filtered blood components, and to the method used to distinguish viable from apoptotic cells.

Apoptosis↗
PubMed2001

Beta-N-acetylhexosaminidase activity and isoenzyme profile in the kidney and urine of trained rats.

Lysosomes play an important role in the immune system functioning and are involved in different aspects of inflammatory reaction, repair processes and tissue damage at various levels. Among various effects, it is known that physical exercise influences the release of different lysosomal components. The aim of this study was to evaluate enzyme activity and isoenzymatic profile of beta-N-acetylhexosaminidase both in kidney and urine of normal and trained rats. Enzyme activity was measured by fluorimetric assay while beta-N-acetylhexosaminidase isoenzymes were separated using DEAE-cellulose chromatography. Hexosaminidase specific activity was significantly increased in urine of trained rats whereas there was no increase in the kidneys of trained rats. Indeed, no significant differences were observed in the isoenzyme profile of kidney and urine extracts from normal and trained rats. Our findings suggest the exercise-induced release of lysosomal enzymes is a functional effect and not due to disruption of lysosomal membranes.

Animals↗
PubMed2001

Plasma endothelin-1 and big endothelin-1 levels in superior and inferior vena cava during protracted antiorthostatic hypokinetic/hypodynamia in rats.

The plasma levels of endothelin-1 and big endothelin-1 were evaluated in blood of rats in the superior and inferior vena cava, in normal posture (synchronous controls), and after 12 days head-down suspension and 1 day recovery in normal posture. In synchronous controls, the mean plasma concentration of endothelin-1 in inferior vena cava or superior vena cava was almost the same (5.89+/-0.63 pmol/l and 5.67+/-0.64 pmol/l, respectively), whereas the mean plasma concentration of big endothelin-1 was higher (p<0.05) in superior vena cava compared to inferior vena cava (5.49+/-0.75 pmol/l and 1.39+/-0.15 pmol/l, respectively). In samples from superior vena cava of head-down suspended rats big endothelin-1 levels were significantly lower (p<0.05) up to day 9 of suspension, compared to non-suspended synchronous controls, whereas endothelin-1 values were higher (p<0.05). Big endothelin-1 concentration was higher (p<0.05) in inferior vena cava compared to non-suspended synchronous controls. The behaviour of endothelin-1 was more complex, endothelin-1 levels were lower (p<0.05) on day 1 of head-down suspension and higher (p<0.05) in samples taken on days 9 and 12. After 1 day recovery endothelin-1 and big endothelin-1 concentrations returned to normal in both superior vena cava and inferior vena cava. These data indicate that the endothelial system involvement for the two venous beds is different and suggest that local rather than systemic evaluation could better explain endothelial involvement and the contribution of different anatomic sites to the biosynthesis, conversion and clearance of the various involved molecules.

Animals↗
PubMed2000

Activity and isoenzyme profile of N-acetyl-beta-D-glucosaminidase in urine from workers exposed to cadmium.

The urinary excretion of N-acetyl-beta-D-glucosaminidase (U-NAG) and urinary Cadmium (U-Cd) concentration, a measure of the metal load in the body, were evaluated in 28 workers exposed to Cd, to determine the relation between the two parameters. In urine from 22 exposed workers with U-Cd<2 microg/g creatinine (Cr) there was no significant difference in U-NAG value (0.98+/-0.59 U/gCr) compared to non-exposed (0.73+/-0.48 U/gCr). In the six workers with 2 microg/gCr < or =U-Cd<10 microg/gCr the U-NAG (2.32+/-0.61 U/gCr) was statistically (P<0.05) higher than in other workers. In both the U-Cd intervals examined there were no altered values of beta2-microglobulin from urine of exposed workers compared to non-exposed (<0.30 mg/l). The U-NAG isoenzymes were separated by DEAE-cellulose chromatography from urine of non-exposed subjects and exposed workers. The U-NAG isoenzyme profile in urine of non-exposed subjects showed a high percentage (about 95%) of the A (acid) form, a much lower percentage (about 4.5%) of B (basic) form and a negligible percentage (about 0.5%) of I (intermediate) form. In the urine of 22 exposed workers with U-Cd<2 microg/gCr, the percentages of U-NAG isoenzymes were not different from non-exposed. In the urine of six workers with 2 microg/gCr< or =U-Cd<10 microg/gCr the percentage (8.34+/-0.91) of isoenzyme B (U-NAG-B), a marker of lesional enzymuria, was statistically increased (P<0.05) compared to non-exposed (4.42+/-0.56). These results suggest that adopting a biological limit for U-Cd equal to 10 microg/gCr might not be sufficiently protective. The increase in U-NAG-B content at 2 microg/gCr<U-Cd</=10 microg/gCr is probably due to a lesion of the proximal tubule caused by the metal which might follow an induction of the apoptotic process.

Acetylglucosaminidase↗
PubMed2000

beta-hexosaminidase, alpha-D-mannosidase, and beta-mannosidase expression in serum from patients with carbohydrate-deficient glycoprotein syndrome type I.

The activity of beta-hexosaminidase, determined with 4-methylumbelliferyl-beta-N-acetylglucopyranoside substrate, and of beta-D-mannosidase was significantly higher in the serum of patients with carbohydrate-deficient glycoprotein (CDG) syndrome type IA (phosphomannomutase deficiency) than in controls. No significant differences were observed in the activity of beta-hexosaminidase, determined using 4-methylumbelliferyl-beta-N-acetylglucopyranoside-6-sulphate as substrate, and the activity of alpha-D-mannosidase. Using DEAE-cellulose chromatography, a greater amount of hexosaminidase B than hexosaminidase A was detected in CDG serum. In CDG serum, hexosaminidase A was eluted in a more basic position in the salt gradient. An isoenzyme of alpha-D-mannosidase and beta-D-mannosidase was identified in control and CDG sera. alpha-D-Mannosidase isoenzyme was eluted in a slightly more basic position in CDG serum than in control serum, whereas beta-D-mannosidase isoenzyme was eluted in the same position.

Adolescent↗
PubMed2000

White cell apoptosis in platelet concentrates.

BACKGROUND: The aim of the present study was the evaluation of the apoptosis in residual white cells (WBCs) contained in platelet concentrates (PCs) and of the relationship of this apoptosis with the concentration of inflammatory cytokines in the medium and with platelet activation. STUDY DESIGN AND METHODS: Three independent methods were used to evaluated apoptosis in WBCs present in 9 PCs, either from single donors by apheresis (SD-PCs) or from pooled buffy coats (BC-PCs). All PCs were divided in two parts, one of which was irradiated. PCs were stored up to 4 days at room temperature, and samples were withdrawn daily for analysis of apoptosis, of platelet activation (surface and soluble CD62P), and of cytokine concentration (interleukin [IL]-1alpha, IL-1beta, IL-6, IL-8, and tumor necrosis factor alpha). RESULTS: Apoptosis was found to occur with storage in both irradiated and nonirradiated units. Platelet activation increased with storage time and was higher in BC-PCs. The amount of released cytokines was rather variable among PC units. Only IL-8 was consistently found to increase with storage time. CONCLUSIONS: Apoptosis of residual WBCs occurred in PC units as a function of storage time. The amount and the time course of apoptosis seem to correlate with IL-8 release rather than with platelet activation or with the occurrence of febrile nonhemolytic transfusion reactions.

Apoptosis↗
PubMed2000

[ELISA analysis of salivary cotinine in smokers].

BACKGROUND: The presence in saliva of cotinine, the main and inactive metabolite of nicotine, reflects the extent of systemic distribution of nicotine and explains the increased susceptibility to periodontal disease in smokers. The aim of this study was to investigate the comparative amount of cotinine in the saliva of habitual cigarette smokers, non-smokers and passive smokers. METHODS: Saliva sample were obtained from 14 cigarette smokers and 13 non-smokers (8 passive-smokers), all without periodontal disease, and analyzed by Microplate EIA (a variation of ELISA based on cross-reactivity of cotinine with anti-cotinine antibody revealed by absorbance in spectrophotometry) to determine the presence and the amount of cotinine. RESULTS: Cotinine was detected in the saliva of smokers with a mean of 92.3 +/- 4.15 ng/ml and, unexpectedly, there was evidence of cotinine also in the saliva of non-smokers (mean 5.4 +/- 1.22 ng/ml), particularly, in passive-smokers (mean 12.9 +/- 6.67 ng/ml). CONCLUSIONS: The salivary concentration of cotinine can be used to estimate nicotine intake and its possible role in the pathogenesis of periodontal disease also in passive-smokers.

Adult↗
PubMed1999

Elevated beta-N-acetylhexosaminidase activity in focal dystonia fibroblasts.

Specific activities of beta-D-hexosaminidase, alpha-D-mannosidase, beta-D-galactosidase and beta-D-glucuronidase were determined in fibroblasts of patients with writer's cramp and torticollis. These diseases show degenerative neurological disorders similar to those observed in lysosomal diseases. Hexosaminidase specific activities, determined using 4-methylumbelliferyl-beta-N-acetylglucopyranoside and 4-methylumbelliferyl-beta-N-acetylglucopyranoside-6-sulphate as substrates, were significantly higher in the fibroblasts of patients than in controls. No significant differences were observed in the specific activities of the other lysosomal enzymes. The increased hexosaminidase specific activities in torticollis and writer's cramp may be additional markers for these diseases.

Adult↗
PubMed1999

Antibodies reactive with neutrophils following allogeneic haematopoietic stem cell transplantation.

Allogeneic haematopoietic stem cell transplants might induce immunological alterations leading to autoimmune-like syndromes. In particular neutrophil-associated antigens could represent the target for autoantibodies against neutrophils in patients receiving an allogeneic peripheral stem cell or bone marrow transplantation, giving rise to granulocytopenia. With this aim we studied prospectively 43 allotransplanted patients for the presence of antibodies reacting with neutrophils (ARN), looking for a correlation with a post-engraftment neutropenia. Our data showed that the direct test for ARN was positive in 30 patients. Interestingly, 7/7 patients who received a T-cell-depleted marrow transplant developed ARN. Antibodies with a specific neutrophil-antigen reactivity were detected in 4 patients, 1 with an anti-CD16/FcbetaRIIIb receptor reactivity and 3 with anti-NA 1 reacting patterns, respectively. From a clinical point of view, it was not possible to demonstrate a close and significant relationship between neutropenia and ARN, although patients showing ARN had slightly lower absolute levels of peripheral neutrophils until 6 months after BMT. In conclusion, ARN may be detected in the majority of patients following allogeneic stem cell transplantation; in addition, since ex vivo or in vivo T-cell-depletion leads to a higher percentage of patients positive for ARN, it could be hypothesized that "autoimmune-like" disorders in transplanted patients might be related to a T-cell derangement due to different numbers and subsets of T lymphocytes.

Adult↗
PubMed1998

Allogeneic peripheral blood stem cell transplantation in patients with early-phase hematologic malignancy: a retrospective comparison of short-term outcome with bone marrow transplantation.

BACKGROUND AND OBJECTIVE: Transplantation of mobilized allogeneic peripheral blood stem cells (PBSC) has recently been reported by several groups. However, few patients receiving an allograft in the early stage of their disease have been described so far. DESIGN AND METHODS: Fifteen patients with early stage hematologic malignancies were transplanted with cryopreserved allogeneic PBSC from HLA-identical siblings. PBSC were collected after priming with 10 micrograms/kg/day of glycosylated granulocyte colony-stimulating factor (G-CSF, lenograstim). Outcomes were compared to a historical control group of 15 patients who received conventional bone marrow transplantation (BMT) from HLA-identical sibling donors. The two groups were matched for diagnosis, stage of disease, age, preparative regimen, graft-versus host (GVHD) prophylaxis, patients' and donors' gender and cytomegalovirus (CMV) serology. Diagnoses in both groups were: chronic myelogenous leukemia (CML) in first chronic phase (= 5), acute leukemia in first complete remission (CR) (= 5), non-Hodgkin's lymphoma in CR (= 1) and multiple myeloma (MM) with sensitive disease (= 4). All patients were given cyclosporin-A (CsA) and methotrexate (MTX) for GVHD prophylaxis. Preparative regimens varied according to diagnosis and included either busulfan/cyclophosphamide combination (BU/Cy) or total body irradiation/cyclophosphamide +/- melphalan (TBI/Cy +/- Mel). RESULTS: The patients in the PBSC group showed a more rapid hematopoietic reconstitution with a significant difference in the median times to 1 x 10(9) neutrophils/L (19 days vs. 26 days; p = 0.03) and to platelet transfusion independence (18 days versus 22 days; p = 0.02). This finding was associated with a significantly shorter hospitalization (28 days versus 33 days after transplantation; p = 0.01). In the PBSC series, grade II-IV acute GVHD occurred in 3 patients (20%) and grade III-IV in 1 patient (7%). In the BMT control group, grade II-IV aGVHD was reported in 2 cases (13%; p = NS) and 1 case had grade III-IV GVHD. Chronic GVHD developed in 7 patients (47%) (limited = 6; extensive = 1) undergoing PBSC transplantation and 5 patients (33%) (limited = 4; extensive = 1) in the BMT series (p = NS). No difference was found in the incidence of grade II-IV (according to the World Health Organization) mucositis, whereas PBSC recipients did have a significantly lower incidence of additional severe (grade III-IV) organ toxicity. After a median follow-up of 300 days (range 180-630), all PBSC patients are still alive with a median Karnofsky score of 100% (range 80%-100%). Thirteen patients are in CR and 2 myeloma patient are in good partial remission (PR). Also, in the BMT group the peritransplant mortality was absent; two MM patients died due to progressive disease at day +796 and +1,023, respectively; one leukemic patient died of chronic GVHD 407 days after transplantation and one additional leukemic individual relapsed 1,140 days after BMT. INTERPRETATION AND CONCLUSIONS: This retrospective comparison suggests that allogeneic PBSC transplantation performed in the early stage of the disease is safe and may be associated with a more rapid hematopoietic reconstitution than BMT, as well as lower transplant-related toxicity and earlier hospital discharge with apparently no increased risk of acute and chronic GVHD.

Adolescent↗