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A Tagliaferri

Publications and source records attributed to A Tagliaferri.

At least 19 recordsLinked to original sources
PubMed2006

Measuring, modelling and testing ozone exposure, flux and effects on vegetation in southern European conditions--what does not work? A review from Italy.

Ozone (O3) exposure at Italian background sites exceeds UN/ECE concentration-based critical levels (CLe(c)), if expressed in terms of AOT40. Yet the occurrence of adverse effects of O3 on forests and crops is controversial. Possible reasons include (i) ability of response indicators to provide an unbiased estimate of O3 effects, (ii) setting of current CLe(c) in terms of cut-off value and accumulation level, (iii) response functions adopted to infer a critical level, (iv) environmental limitation to O3 uptake and (v) inherent characteristics of Mediterranean vegetation. In particular, the two latter points suggest that critical levels based on accumulated stomatal flux (CLe(f)) can be a better predictor of O3 risk than CLe(c). While this concept is largely acknowledged, a number of factors may limit its applicability for routine monitoring. This paper reviews levels, uptake and vegetation response to O3 in Italy over recent years to discuss value, uncertainty and feasibility of different approaches to risk assessment.

Crops, Agricultural↗
PubMed2006

Predictors of postabsorptive ghrelin secretion after intake of different macronutrients.

CONTEXT: Release of ghrelin, a gastrointestinal hormone regulating feeding and energy balance, is blunted in obesity, a condition associated with insulin resistance. OBJECTIVE: The objective was to identify anthropometric and metabolic predictors of postabsorptive ghrelin secretion. DESIGN: We evaluated ghrelin, insulin, glucose, and leptin secretion overnight and after intake of different macronutrients. SUBJECTS: Ten obese subjects (age, 31.8 +/- 2.5 yr; body mass index, 43.4 +/- 0.8 kg/m(2)) and six lean subjects (age, 33.5 +/- 2.4 yr; body mass index, 21.8 +/- 1.4 kg/m(2)) participated in the study. MAIN OUTCOME MEASURES: The main outcome measures were resting energy expenditure (REE); fat mass; nighttime approximate entropy (ApEn) and synchronicity (cross-ApEn) of ghrelin, insulin, and leptin; insulin sensitivity by homeostatic model approach insulin-sensitivity (HOMA-S%); postabsorptive area under the curve (AUC); and Delta of ghrelin, insulin, glucose, and leptin after carbohydrate-, lipid-, and protein-rich test meals. RESULTS: Nighttime ApEn scores were higher in obese than lean subjects (P < 0.01). Cross-ApEn revealed a synchronicity between ghrelin-insulin, ghrelin-leptin, and insulin-leptin in both groups. Compared with baseline, ghrelin decreased significantly (P < 0.01) in lean and obese subjects after carbohydrates (42.2 vs. 28.5%; P < 0.05), lipids (40.2 vs. 26.2%; P < 0.01), and proteins (42.2 vs. 26.3%; P < 0.01) devoid of between-meal ghrelin differences. Significant associations occurred between nocturnal ghrelin ApEn and insulin (r = 0.53; P < 0.05), postmeal ghrelin AUCs and REE (r = -0.57; P < 0.05), and HOMA-S% (r = 0.52; P < 0.05), postmeal ghrelin Delta and HOMA-S% (r = 0.60; P < 0.05). REE (beta = -0.57; P = 0.02) and ghrelin ApEn (beta = -0.62; P = 0.01) were predictors of postmeal ghrelin AUC and Delta, respectively. CONCLUSIONS: Obesity determined a decreased orderliness of ghrelin secretion and a relative loss of ghrelin-insulin synchrony. Postabsorptive ghrelin secretion decreased significantly both in obese and lean subjects, was related to insulin sensitivity, and was predicted by energy expenditure and hormone pulsatility.

Adult↗
PubMed2006

[Haemocoagulative modifications correlated with pregnancy].

AIM: The aim of this paper was to establish the physiologic changes in the coagulation and fibrinolytic systems during normal pregnancy. METHODS: One-hundred and twenty normal pregnant women were investigated in a longitudinal study involving 3 measurements: blood samples were collected at 12, 24 and 36 weeks of gestation and were assayed for prothrombin time, antithrombin III (ATIII) activity, protein C activity, protein S (PS) activity, prothrombin fragments 1+2, type 1 plasminogen activator inhibitor activity, tissue plasminogen activator antigen, plasminogen, activated protein C resistance, factors VII and VIII levels and D dimer. Student t-test, one way analysis of variance (ANOVA) and Fisher test were used for statistical analysis. RESULTS: Factor VII and factor VIII were always increased with respect to controls. Variance analysis showed a statistically significant reduction for anticoagulants (PS) and a rise for F1+2 and D dimer. With regard to fibrinolysis, there was an increase both for t-PA and PA1-1 during pregnancy. Moreover, the increased activity of factors of haemostasis was accompanied by an increase of activity and concentration of ATIII and acquired activated protein C resistance. CONCLUSIONS: These findings suggest that normal pregnancy is associated with an hypercoagulable state, resulting into a moderate risk for thrombosis during the different trimesters of pregnancy. Also broad spectrum assays which measure a range of trombin/fibrin formation in serum have become an established mean to identify activation of blood coagulation and/or fibrinolysis. There is a considerable interest in the application of these assays to the diagnosis of other acquired hypercoagulable states; such as thrombophilia during pregnancy. From the viewpoint of coagulation/fibrinolysis changes, the follow-up of thrombophilia markers could be recommended when levels of coagulation parameters exceed the normal values during pregnancy.

Adult↗
PubMed2006

[Hypercoagulability during pregnancy: evidences for a thrombophilic state].

AIM: The development of thrombotic disorders is a major threat for young women during pregnancy. It is one of the main causes of pregnancy-related disorders, which may also result in harm for the conceptus. Successful pregnancies require an even balance of coagulation and fibrinolysis, in order to secure stabilization of the basal plate as well as adequate placental perfusion. Broad spectrum assays which measure a range of thrombin/fibrin formation in serum have become an established means of identifying activation of blood coagulation and/or fibrinolysis. There is considerable interest in the application of these assays to the diagnosis of other hypercoagulable states, such as thrombophilia during pregnancy. We investigated coagulation/fibrinolysis parameters for significant differences between pregnant women during their gestation (first, second and third trimester) with or without pregnancy loss and healthy nonpregnant women. METHODS: Thirty-nine pregnant women, aged 24-39 years, were studied. They were subdivided according to pregnancy trimester: 15 patients in the first trimester; 13 in the second and 11 in the third. The selection of patients was carried out in cooperation with the Transfusion Center of the Second University of Naples in order to obtain a homogeneous sample group. The control group included 400 healthy patients. Biochemical and blood coagulation tests were performed for each patient and the results obtained were compared with the control group. RESULTS: A decrease in free protein S (PS) and fibrinolysis (t-PA/PAI-1) activities and an increase in Factor VII, Factor VIII, prothrombin fragment 1+2 (F1+2), D-dimer (D-dimer) were observed in pregnant women during the follow-up of gestation. However, there were statistical differences between the groups of women with one or more pregnancy loss where it was found the lowest values in t-PA and PAI and the highest values in FVII and F1+2. Among subjects with more than one abortion, coagulation/fibrinolysis derangements before the partum were more prominent. A significant association exists between consecutive recurrent abortions and pregnancy complications such as placental abruption, hypertensive disorders and CS. This association persists after controlling for variables considered to coexist with recurrent abortions. CONCLUSIONS: These findings suggest that an excessive hypercoagulable state is associated with the termination of pregnancy resulting into a moderate risk for thrombosis during the different trimesters of pregnancy. The follow-up of fibrinolytic markers could represent a useful diagnostic tool for termination of pregnancy.

Blood Coagulation↗
PubMed2005

Femtosecond dynamics in ferromagnetic metals investigated with soft x-ray resonant emission.

We present measurements of the magnetic circular dichroism in x-ray resonant emission in the perpendicular geometry (circularly polarized x rays at normal incidence to the magnetization) for L(2,3) the absorption region in Fe, Co, and Ni metal. The results show that spin-dependent screening of the core hole takes place within the scattering time scale, which is supported by the absence of the effect in ionic systems. This allows an assessment of the time scale for the screening process (up to a few femtoseconds). The process is almost complete within the scattering time for Fe and Co, but this is not the case for the narrow band metal Ni which shows a much slower dynamics.

Journal Article↗
PubMed2005

Dental procedures in adult patients with hereditary bleeding disorders: 10 years experience in three Italian Hemophilia Centers.

Excessive bleeding after dental procedures are one of the most frequent complications occurring in patients with hereditary bleeding disorders. In this retrospective study we collected data from 10 years of experience in the oral care of patients with congenital haemorrhagic disorders in three Italian Hemophilia Centers. Between 1993 and 2003, 247 patients with inherited bleeding disorders underwent 534 dental procedures including 133 periodontal treatments, 41 conservative dentistry procedures, 72 endodontic treatments and 288 oral surgery procedures. We recorded 10 bleeding complications (1.9%), most of which occurred in patients with severe/moderate haemophilia A undergoing multiple dental extractions. Thus, our protocol of management of patients with hereditary bleeding tendency undergoing oral treatment or surgery has been shown to be effective in preventing haemorrhagic complications.

Adolescent↗
PubMed2004

Low energy electronic excitations in the layered cuprates studied by copper L3 resonant inelastic x-ray scattering.

We have measured the resonant inelastic x-ray scattering (RIXS) spectra at the Cu L3 edge in a variety of cuprates. Exploiting a considerably improved energy resolution (0.8 eV) we recorded significant dependencies on the sample composition and orientation, on the scattering geometry, and on the incident photon polarization. The RIXS final states correspond to two families of electronic excitations, having local (dd excitations) and nonlocal (charge-transfer) character. The dd energy splitting can be estimated with a simple crystal field model. The RIXS at the L3 edge demonstrates here a great potential, thanks to the resonance strength and to the large 2p spin-orbit splitting.

Journal Article↗
PubMed2004

Unraveling orbital ordering in La0.5Sr1.5MnO4.

Orbital ordering (OO) in the layered perovskite La0.5Sr1.5MnO4 has been investigated using the enhanced sensitivity of soft x-ray resonant diffraction at the Mn L edges. The energy dependence of an OO diffraction peak over the L(2,3) edges is compared to ligand-field calculations allowing a distinction between the influences of Jahn-Teller distortions and spin correlations. The energy dependence of the diffraction peak at the Mn L1 edge is remarkably different from that observed at the Mn K edge.

Journal Article↗
PubMed2004

[Thrombophilic syndrome associated to phenotypic resistance to activated protein C in postmenopausal women].

AIM: Hormone replacement therapy (HRT) may reduce the risk of cardiovascular events in healthy postmenopausal women. However recent studies suggest a 2-4 fold increased risk of idiopathic venous thromboembolism (VTE) among users of HRT. Our aim was to evaluate the overall effect of HRT on hemostatic variables probably related to increased VTE risk reported in epidemiological studies. METHODS: Therefore, 100 healthy postmenopausal women aged 45-60 years divided into 50 HRT non-users and 50 HRT users were examined. The authors assayed on the automated coagulometer ACL7000 (Instrumentation Laboratory, Milan) the procoagulant proteins: factor VIII (VIII:C) and factor VII (VII:C); the natural anticoagulant proteins: antithrombin (ATIII), protein C (PC), protein S (PS) and the resistance to anticoagulant action of activated protein C (APC-Resistance). The free tissue factor pathway inhibitor (TFPI) was measured with an ELISA method (Diagnostica Stagò; France, Roche). The in vivo coagulation and fibrinolysis activation was evaluated by the assays of prothrombin fragment 1+2 (F1+2) and plasmin- antiplasmin complexes (PAP) using ELISA techniques. RESULTS: Increased levels of FVIII:C and FVII:C were observed in HRT users and HRT non-users women compared to controls (FVIII:C= 126+/-58%, 120+/-59% vs 85+/-15% p=0.0001; FVII: C 113+/-23%, 103+/-19% vs 90+/-16% p=0.0001). The activation peptides were significantly different compared to those found in control subjects; higher values were observed in HRT users compared to HRT non-users (F1+2=1.11+/-0.44 nM, 077+/-0.31 nM vs 0.45+/-0.35 p=0.00001; P-AP= 606+/-406 ng/ml, 514+/-205 ng/ml vs 235+/-59 p=0.0001). The ATIII and the PC were similar among the 3 different groups of subjects, but reduced levels of PS were observed in HRT users (PS 93+/-23%, 105+/-22% vs 109+/-12 p=0.0001). The mean normalized APC sensitivity ratio (APC-SR) was lower in the two populations of women as compared with that of controls (nAPC-SR 1.02+/-0.7, 1.02+/-0.8 vs 1.1+/-25 p=0.02). The values of free TFPI were reduced in HRT users compared to HRT non-users (9.1+/-1.9 ng/ml, 10.1+/-2.3 ng/ml vs 4.6+/-1.5 ng/ml p<0.0001). CONCLUSION: HRT appears to be associated to a shift in the procoagulant-anticoagulant balance towards a procoagulant state. The changes in hemostatic system could explain the increased risk of VTE in healthy postmenopausal women during HRT, nevertheless this risk could be higher in women known to have a congenital or acquired thrombophilic state.

Activated Protein C Resistance↗
PubMed2003

Perpendicular interlayer coupling in Ni80Fe20/NiO/Co trilayers.

An in-plane perpendicular magnetic coupling between Ni80Fe20 and Co has been found in NiFe/NiO/Co trilayers for a NiO thickness ranging from 4 to 25 nm by magneto-optical Kerr effect and x-ray magnetic circular dichroism measurements. In the easy magnetization direction of the Co layer, the Co coercive field H(C) increases when the thickness of the NiO layer t(NiO) increases. Because of the coupling, H(C) is always larger than for NiO/Co bilayers with the same thicknesses. The saturation field of the NiFe layer H(S) decreases when t(NiO) increases, indicating a weakening of the coupling. Numerical simulations show that the presence of interface roughness combined with a small value of the NiO anisotropy can explain the observed 90 degrees coupling.

Journal Article↗
PubMed2003

Sum rules in x-ray resonant Raman scattering: recovering the Co ground state information in CoFe2O4 as a test case.

We present an approach to x-ray resonant Raman scattering suitable for sum-rule analysis. In magnetic systems it gives ground state information as represented by an expansion in coupled multipoles of orbital and spin moments. The experiment is based on the angular dependence of the integrated peak intensities. In 3d transition elements one obtains information up to order 4 from the channel 2p(6)3d(n)-->2p(5)3d(n+1)-->2p(6)3s(1)3d(n+1). By combining these results with L(2,3) absorption dichroism, we show quantitatively the atomiclike properties of cobalt in CoFe2O4 up to high-order multipoles.

Journal Article↗
PubMed2003

Lack of association between UCP2 gene polymorphisms and obesity phenotype in Italian Caucasians.

The importance of the genetic component on adipose tissue accumulation has been clearly demonstrated. Among the candidate genes investigated, there are those that regulate thermogenesis and, thus, can affect energy expenditure. The uncoupling proteins (UCPs) are a family of proteins that uncouple respiration leading to generation of heat and increased energy expenditure. Contradictory data indicate that allelic variants in their coding genes might be associated with obesity. In this study we evaluated the role of two allelic variants of the UCP2 gene in obesity and the association with its sub-phenotypic characteristics. To this aim, 360 morbidly obese patients [age: 45 +/- 15 yr, body mass index (BMI): 46 +/- 7 kg/m2] and 103 normal weight subjects (BMI < 24 kg/m2) were genotyped for the 45 bais-pair (bp) insertion/deletion (I/D) in the 3'-untraslated region of exon 8 of the UCP2 gene while the presence of an Ala/Val substitution at codon 55 (Ala55Val) of the same gene was studied in 104 obese and 50 lean subjects. Patients also underwent a study protocol including measurements of BMI, waist-to-hip ratio (WHR), resting energy expenditure (REE), energy intake, fat mass (FM) and free fat mass (FFM), total cholesterol (TCH), high density lipoprotein (HDL) cholesterol, triacylglyceroles (TG), leptin levels, basal glucose, immunoreactive insulin (IRI), glycated haemoglobin (HbA1c), insulin sensitivity and thyroid hormones. No significant association between the two polymorphisms studied and the clinical, metabolic and anthropometric parameters characteristic of the obese phenotype was found. These results, in accordance with similar findings previously obtained in other ethnic groups, suggest that these two UCP2 allelic variants may not have a direct role in the pathogenesis and development of obesity.

Adult↗
PubMed2002

Interferon and ribavirin in HIV-negative haemophiliacs with chronic hepatitis C who were nonresponders to a previous interferon treatment.

Between January 1999 and December 2001, 33 HIV-negative haemophiliacs with interferon-nonresponsive chronic hepatitis C were treated with interferon (IFN) alpha2b (5 MU three times weekly) and ribavirin (1-1.2 g daily) for 12 months. Four patients (12.1%) dropped out of the study due to adverse effects. At the end of therapy, normalization of ALT occurred in 14/33 treated patients (42.4%) and HCV-RNA was cleared in 12 (36.4%). Eleven patients (33.3%) became sustained responders. Genotype 1 was the only factor associated with a poor response to therapy (P < 0.001). Our study shows that IFN and ribavirin combination therapy is effective in HIV-negative chronically HCV-infected haemophiliacs who do not respond to a previous IFN treatment.

Adult↗
PubMed2001

The natural history of chronic hepatitis C in a cohort of HIV-negative Italian patients with hereditary bleeding disorders.

This study looked at 102 anti-hepatitis C virus (HCV)-positive, hepatitis B virus (HBV)-negative, and HIV-negative patients (median age, 45.1 years; range, 15-71) affected by hereditary bleeding disorders who have been infected with HCV for 15 to 34 years (median, 25.1). All these patients were infected before the mid 1980s because of non-virally inactivated pooled blood products. Fourteen patients (13.7%) were HCV-RNA negative with no signs of liver disease and were considered to have cleared the virus. Eighty-eight patients (86.3%) were HCV-RNA positive. The HCV genotype distribution was 1a in 20.5%, 1b in 36.4%, 2 in 17.0%, 3 in 15.9%, 4 in 3.4%, and mixed in 6.8% of cases. Twenty-four patients (23.5%) had serum cryoglobulins, symptomatic in 4 cases, and associated with liver disease and with genotype 1. Among the 88 HCV-RNA-positive patients, 15 (17.0%) had normal alanine aminotransferase levels and abdominal ultrasound, 61 (69.3%) had nonprogressive chronic hepatitis, and 12 (13.7%) had severe liver disease (6 [6.9%] liver cirrhosis, 4 [4.5%] hepatic decompensation, and 2 [2.3%] hepatocellular carcinoma) after a follow-up period of 25 years. There were 3 (3.4%) liver-related deaths. HCV genotype 1, patient's age at evaluation, duration of infection, and severity of congenital bleeding disorder were associated with more advanced liver disease. The results confirm the slow progression of HCV infection in HIV-negative hemophiliacs.

Adolescent↗
PubMed1996

Isochromosome 15q of maternal origin in a Prader-Willi patient with pituitary adenoma.

We report on a Prader-Willi syndrome (PWS) patient carrier of a balanced 15q15q translocation and affected by a prolactin-secreting pituitary adenoma. Evidence provided by molecular studies indicates that the structural rearrangement is an isochromosome of maternal origin. According to the identification of isodisomy as the basis of the association of rare disorders and the recent report on chromosome 15 monosomy and nullisomy in pituitary adenoma, we suggest that in our case PWS and pituitary adenoma might be related.

Adenoma↗
PubMed1996

[pT1G3 bladder carcinoma: parameters of a correct therapy].

Between 13.8% and 27% of all superficial bladder cancers are represented by pT1G3 neoplasm. In the Department of Urology of Policlinico S. Marco-Zingonia, between February 1988 and June 1994, we treated 22 patients suffering for pT1G3 bladder tumor. TUR-B has demonstrated to be a good approach for treatment of superficial bladder cancer, with low morbility; on the opposite side, we have to underline the high rate of recurrence and of progression of the urothelium disease. Now a day our best approach for the treatment of pT1G3 bladder tumor is represented by radical cystectomy supplied by chemotherapy.

BCG Vaccine↗
PubMed1996

[Orthotopic ileal neobladder of the Emikock type: technical points and functional results].

Ileal orthotopic neobladder represents, nowadays, the best urinary diversion after cystectomy. Emikock procedure was performed, in our institution, in 26 patients with bladder cancer T2-T4. At 6-60 months of follow-up 3 pts were died with local or at distance neoplastic recurrence, 2 were alive with neoplasms and 21 were NED. Nocturnal continence was good in 22 cases (88%) and only 3 patients were obstructed because of pseudodyssynergia in 2 and stricture in 1. Emikock neobladder even if needs a longer surgical time than other procedure and a long ileal tract is almost free from severe metabolic disorders. This technique offers a good protection of high urinary tract because of antireflux nipple and avoid the uretero-intestinal stricture. It not feasible, now, to know the functional trend of this reservoir on the long term. Adequate postoperative training is recommended to avoid the pseudodyssynergia and functional obstruction of reservoir.

Adult↗