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Lucrezia Furian

Publications and source records attributed to Lucrezia Furian.

11 recordsLinked to original sources
PubMed2006

Co-administration of sirolimus alters tacrolimus pharmacokinetics in a dose-dependent manner in adult renal transplant recipients.

A combination of tacrolimus (TAC) and sirolimus (SIR) has recently proved to be a very effective immunosuppressive regimen in organ transplantation. In pediatric transplant recipients, co-administration of these two drugs has been shown to result in a significant decrease of exposure to TAC, whereas conflicting data have been obtained regarding this pharmacokinetic interaction in adults. The aim of this study was to investigate the effect of SIR on TAC pharmacokinetics in adult transplant recipients. Sixteen adult patients (mean age 38+/-8 years), who had been on standard TAC plus low-dose SIR immunosuppressive treatment for 6 months after renal transplantation, were enrolled for a TAC pharmacokinetic study before and 15 days after discontinuing SIR. Eight patients had received SIR 0.5 mg day(-1) and eight patients 2 mg day(-1). TAC doses remained the same in all patients after SIR withdrawal. After discontinuing SIR, statistically significant, dose-dependent increases were observed in area under the curve (AUC), peak (C(max)) and trough (C(min)) TAC concentrations (+15-20% and +27-32%, after discontinuing the 0.5 and the 2 mg day(-1) doses, respectively). Proportional decreases were consistently observed in apparent oral clearance (-13% and -23%). Very good correlations were found between TAC AUC and C(min), both before and after SIR withdrawal (R(2)=0.94, P<0.0001 and R(2)=0.97, P<0.0001, respectively). Our findings clearly demonstrate that the SIR-induced reduction in TAC exposure also takes place in adults and is, therefore, a general, age-independent phenomenon. Hence, TAC levels need to be carefully monitored in transplant recipients of any age, in order to avoid possible TAC overexposure upon SIR discontinuation.

Adult↗
PubMed2006

Perforin, Granzyme B, and fas ligand for molecular diagnosis of acute renal-allograft rejection: analyses on serial biopsies suggest methodological issues.

BACKGROUND: The Perforin-Granzyme B and Fas/Fas Ligand apoptotic mechanisms are involved in the development of acute renal rejection (AR). We describe our experience of analyzing the expression of cytotoxic T-lymphotoxins (CTL) in biopsies and peripheral blood leukocytes (PBL) for the diagnosis of AR. METHODS: We analyzed Perforin (P), Granzyme B (GB) and Fas Ligand (FL) expression in 68 renal biopsies and 64 PBL using comparative kinetic RT-PCR and, for GAPDH and FL, we also replicated with real-time RT-PCR. The levels of expression were measured in different groups, such as T0 (biopsies before reperfusion and PBL in recipient before the transplant [Tx]), Td (biopsies and PBL collected for clinical purposes) and Tp (biopsies and PBL two months after Tx). RESULTS: A higher CTL expression was seen in non-rejecting (NR) biopsies in the first 2 months after Tx. P and FL were significantly more expressed during AR in all biopsies and in Td, while P remained upregulated in Tp. In PBL, there was no significant increase in CTL transcription during AR. A variable expression of CTL emerged in all T0 biopsies. CONCLUSIONS: Two lytic pathways are activated in biopsies when AR occurs shortly after Tx, whereas the P/GB mechanism prevails if it occurs later on. Only P and FL in biopsies might be able to predict AR diagnosis, but with a considerable variability in each sample, possibly due to the small portion of tissue core, which may be inadequate for molecular diagnosis. CTL expression in PBL does not correlate with histological AR.

Acute Disease↗
PubMed2006

Allograft rejection requires STAT5a/b-regulated antiapoptotic activity in T cells but not B cells.

STATs play key roles in immune function. We examined the role of STAT5a/b in allograft rejection. STAT5a/b-deficient mice showed a 4-fold increased survival time of heart allografts (p < 0.01). Unlike wild type, purified STAT5a/b-/- T cells transferred to Rag1-/- recipients failed to mediate heart allograft rejection until supplemented with STAT5a/b-/- B cells. In vitro, STAT5a/b-/- T cells did not proliferate in response to Con A or alloantigens but entered apoptosis within 48 h (95%). Activated STAT5a/b-/- T cells showed increased expression of proapoptotic (caspases, DNA repair genes, TNF/TNFR-associated factor family genes) and decreased antiapoptotic mRNAs in microarrays, while Western blots confirmed reduced antiapoptotic Bcl-2 and elevated proapoptotic Bax protein expression. Interestingly, at 24 h postactivation, STAT5a/b+/+ and STAT5a/b-/- T cells produced similar levels of IL-2, IL-4, IL-10, and IFN-gamma mRNA; ELISPOT assay showed an equivalent number of IL-4- and IFN-gamma-producing T cells in both STAT5a/b+/+ and STAT5a/b-/- splenic populations. Sera from STAT5a/b+/+ and STAT5a/b-/- rejectors had donor-specific IgM, IgG1, IgG2a, and IgG2b Ab, while STAT5a/b deficiency had no impact on B cell survival or proliferation in response to LPS. Compared with allografts from STAT5a/b+/+ recipients, heart allografts from STAT5a/b-/- recipients had markedly reduced infiltration by CD4 and CD8 T cells but increased infiltration by B cells and dense endothelial deposition of C4d, a marker of humoral rejection. Thus, activated STAT5a/b-/- T cells produce cytokines prior to entering apoptosis, thereby promoting differentiation of B cells yielding donor-specific IgM and IgG Ab that mediate allograft rejection.

Adoptive Transfer↗
PubMed2006

Monolateral placement of both kidneys in dual kidney transplantation: low surgical complication rate and short operating time.

Dual kidney transplantation (DKT) from marginal donors is increasingly used at many centers to help cope with the organ shortage problem. The disadvantages of DKT consist in longer operating times and the risk of surgical complications. DKT can be performed in two ways, i.e. using monolateral or bilateral procedures. From October 1999 to June 2005, 58 DKTs were performed at our unit. In 29 cases (group I), the kidneys were extraperitoneally placed bilaterally in the iliac fossae via two separate incisions; as of June 2003, monolateral kidney placement was preferred in 29 cases, whenever compatible with the recipient's morphological status (group II). After a mean follow-up of 51 +/- 19 months for group I and 15 +/- 7 months for group II, all patients are alive with 1-year graft survival rates of 93% and 96%, respectively. Mean operating times were 351 +/- 76 min in group I and 261 +/- 31 min in group II (P = 0.0001). The mean S-creatinine levels in groups I and II were 132 +/- 47 and 119 +/- 36 mumol/l, respectively, at 1 year. We observed eight surgical complications in group I and seven in group II. Both techniques proved safe, with no differences in surgical complication rates. The monolateral procedure has the advantage of a shorter operating time and the contralateral iliac fossa remains available for further retransplantation procedures.

Aged↗
PubMed2006

Melanoma growth and tumorigenicity in models of microgravity.

INTRODUCTION: Spaceflight involves numerous biological stressors that could affect long-term cancer incidence and tumor behavior. Ground-based models of microgravity can be used to investigate in vitro and in vivo tumor growth as a preparation for later work in space. The incidence of tumor growth and carcinogenesis in microgravity is as yet unknown. Hence, we investigated the effects of modeled microgravity on tumor growth and tumorigenicity using ground-based in vitro and in vivo models. METHODS: Murine B16-F10 melanoma cells were cultured in a tissue culture flask (FL) and in a rotating-wall vessel bioreactor (BIO) designed by NASA to simulate some aspects of microgravity. We then measured cell growth, melanin production, and apoptosis. After 48 h of cultures in FL and BIO, cells were inoculated subcutaneously in C57BL/6 mice, syngeneic hosts for B16-F10 tumor cells. Tumor sizes were then measured every other day. RESULTS: BIO cultures had 50% decreases in growth when compared with FL cultures while demonstrating an inversely proportional increase in doubling time. Melanin production (a marker of differentiation) increased at 24 and 48 h in BIO. Flow cytometry analysis demonstrated that there was an increase in the percentage of apoptotic cells in the BIO when compared with that in the FL. When BIO-cultured melanoma cells were inoculated subcutaneously in mice, there was a significant increase in tumorigenicity as compared with FL-cultured cells. CONCLUSION: Our results indicate that simulated microgravity may have altered the tumor cell characteristics and enhanced the invasive property. It is possible that the microgravity analogue culture environment may have selected highly tumorigenic cells for survival despite the decreased overall growth in the microgravity analogue.

Animals↗
PubMed2005

The Mannich base NC1153 promotes long-term allograft survival and spares the recipient from multiple toxicities.

JAK3 is a cytoplasmic tyrosine kinase with limited tissue expression but is readily found in activated T cells. Patients lacking JAK3 are immune compromised, suggesting that JAK3 represents a therapeutic target for immunosuppression. Herein, we show that a Mannich base, NC1153, blocked IL-2-induced activation of JAK3 and its downstream substrates STAT5a/b more effectively than activation of the closely related prolactin-induced JAK2 or TNF-alpha-driven NF-kappaB. In addition, NC1153 failed to inhibit several other enzymes, including growth factor receptor tyrosine kinases, Src family members, and serine/threonine protein kinases. Although NC1153 inhibited proliferation of normal human T cells challenged with IL-2, IL-4, or IL-7, it did not block T cells void of JAK3. In vivo, a 14-day oral therapy with NC1153 significantly extended survival of MHC/non-MHC mismatched rat kidney allografts, whereas a 90-day therapy induced transplantation tolerance (>200 days). Although NC1153 acted synergistically with cyclosporin A (CsA) to prolong allograft survival, it was not nephrotoxic, myelotoxic, or lipotoxic and did not increase CsA-induced nephrotoxicity. In contrast to CsA, NC1153 was not metabolized by cytochrome P450 3A4. Thus, NC1153 prolongs allograft survival without several toxic effects associated with current immunosuppressive drugs.

Animals↗
PubMed2005

Methoxyethyl-modified intercellular adhesion molecule-1 antisense phosphorothiateoligonucleotides inhibit allograft rejection, ischemic-reperfusion injury, and cyclosporine-induced nephrotoxicity.

BACKGROUND: The addition of phosphorothioate (PS) groups to natural phosphodiester (PD) antisense oligodeoxynucleotides (oligo) prevents their in vivo hydrolysis by nucleases allowing an RNase-dependent elimination of targeted mRNA. To further improve oligo function 2'-methoxyethyl (ME) groups were attached to selected nucleotides at the 3'-end because ME groups block RNase activity. METHODS/RESULTS: ME modification of PS- or PD/PS-oligo targeting human intracellular adhesion molecule (ICAM)-1 mRNA significantly increased the degree and duration of the in vitro inhibitory effects without compromising selectivity and specificity. A 7-day intravenous or oral therapy with rat ME/PS-modified ICAM-1 antisense oligo extended the survivals of kidney allografts. In addition, ME/PS-modified ICAM-1 antisense oligo reduced ischemic-reperfusion injury in kidneys, as measured by glomerular filtration rate, creatinine levels, and infiltration with leukocytes. Finally, a 14-day treatment with cyclosporine (CsA)-induced nephrotoxicity in syngeneic kidney transplants correlated with both increased ICAM-1 protein expression and infiltration with leukocytes. Graft perfusion and treatment of recipients with ICAM-1 antisense ME/PS-oligo alleviated the nephrotoxic effect and decreased ICAM-1 expression and leukocyte infiltration. CONCLUSIONS: ME/PS-modified ICAM-1 antisense oligo is very effective in inhibiting the ICAM-1-dependent mechanism of graft infiltration and tissue damage involved in allograft rejection, ischemic-reperfusion injury, and CsA-induced nephrotoxicity.

Animals↗
PubMed2004

Acute rejection and graft survival in renal transplanted patients with viral diseases.

Transplanted patients are susceptible to viral infections; thus, the aim of this study was to evaluate the features of acute rejections and the outcome of the renal graft in transplanted patients with herpes virus diseases. Renal biopsies from 30 renal transplanted patients undergoing early acute rejection (type IA and IB according to the Banff 97 classification) were evaluated. In total, 15 of these patients experienced cytomegalovirus (CMV) or Epstein-Barr virus disease within the first year following transplantation (group I) and 15 patients showed no evidence of viral infection (group II). No significant differences between the groups in terms of age, male/female ratio, living/cadaveric donor ratio, cold ischemia time, HLA A-B matching, pretransplant panel reactive antibody test, occurrence of post-transplant tubular necrosis, plasma levels of cyclosporin A and mean percent increase of serum creatinine at the time of the biopsy were observed. In group I biopsies, the mean number of interstitial plasma cells, as well as the mean number of CD79a-positive cells (B lymphocytes and plasma cells) was significantly higher than in group II (P<0.01 and <0.01, respectively). There was a positive correlation between the number of infections and the number of plasma cells (P<0.05). In transplanted patients, CMV can trigger the formation of anti-endothelial cell antibodies, which have been proposed to play a role in antibody-mediated rejections. We investigated whether a deposition of C4d, a marker of antibody-mediated reactions, was present in renal peritubular capillaries. In group I C4d deposition was found in five cases, while in group II it was not observed (P<0.05). In group I, 7/15 patients developed chronic allograft nephropathy vs 1/15 patients in group II (P<0.05). The estimated 1-, 5- and 8-year cumulative graft survival rates were 80, 66 and 57%, respectively, in group I, while in group II the estimated 8-year cumulative survival rate was 100% (P<0.05). In conclusion, acute rejection biopsies of patients with viral infections displayed plasma cell infiltrates and, in several cases, C4d deposition. Our study suggests a role of B lymphocytes in the pathology of these rejections and confirms the association between viral infections and poor graft survival.

Adult↗
PubMed2004

Evaluation of 84 elderly donors in renal transplantation.

BACKGROUND: The use of elderly donors (ED) and dual kidney transplantation (DKT) procedures have become common in clinical practice. A correct evaluation of kidneys from ED is crucial to avoid unsuccessful transplantation or the use of DKT when a single transplant (ST) would be equally successful. The aim of this investigation was to assess the role of renal biopsy (RB) in the assessment of kidneys from ED. PATIENTS AND METHODS: A total of 84 ED aged > or = 60 yr were evaluated. In 19 cases, the kidneys were not used, mainly because of atherosclerotic vascular lesions. A histological score (HS) from 0 to 12 was awarded, considering the proportion of glomerulosclerosis, tubular atrophy, interstitial fibrosis, and arterial and arteriolar narrowing. On the basis of the HS, 37 donors were selected for 40 ST and 21 for DKT, three were discarded. All recipients received triple-drug therapy based on calcineurin inhibitors, mycophenolate mofetil and steroids. RESULTS: Primary non-function was observed in three of 40 ST and one of 21 DKT. Acute tubular necrosis occurred in 22/40 ST and in 11/21 DKT. Acute rejection occurred in 16/40 ST and four of 21 DKT. Renal function was satisfactory in both groups, with 1-yr S-Cr = 171 micromol/L and 137 micromol/L, respectively in the ST and DKT groups. One-year patient survival was 92% in ST and 100% in DKT; 1-yr graft function was 87% in ST and 95% in DKT. CONCLUSION: The histological assessment of kidneys from ED enables a correct selection of kidneys for ST or DKT and prevents the transplantation of high-risk kidneys.

Age Factors↗
PubMed2003

Plasma fibrinolytic capacity in renal transplant recipients: effect of steroid-free immunosuppression therapy.

BACKGROUND: Cardiovascular disease is the most common cause of death among renal transplant recipients (RTRs). Impaired fibrinolytic capacity caused by an increase in plasminogen activator inhibitor type 1 (PAI-1) levels is involved in the onset of atherosclerosis and thrombotic complications. Long-term steroid treatment may induce arterial hypertension and metabolic and prothrombotic changes (including up-regulation of PAI-1 synthesis), which increase the cardiovascular risk. We evaluated plasma fibrinolytic behavior in two groups of RTRs treated with different immunosuppressive regimens. METHODS: Twenty-seven RTRs were randomized to receive long-term (17 patients) or perioperative short-term (10 patients) steroids in addition to immunosuppression with cyclosporine A plus everolimus (Certican; Novartis, Basel, Switzerland) (7 patients) or FK506 plus mycophenolate mofetil (20 patients). In each patient, fibrinolytic capacity was studied with the 20-min venous occlusion test 1 and 6 months after transplantation. The following were assayed: euglobulin lysis time, tissue-type plasminogen activator antigen, and PAI-1 antigen and activity. RESULTS: One month after transplantation, a severe impairment of fibrinolytic capacity, mainly caused by an increase in PAI-1 antigen and activity levels, was seen in patients with and without steroid treatment. Six months after transplantation, an improvement in fibrinolytic potential as the result of a decrease in PAI-1 levels was observed only in patients without steroid therapy. None of the steroid-treated patients demonstrated PAI-1 values correlating with body mass index, blood pressure, and metabolic parameters, thus confirming the effect of exogenous factors on PAI-1 expression. Moreover, all patients revealed a slight impairment of stimulated endothelial tissue-type plasminogen activator release, regardless of any steroid treatment, which was probably attributable to calcineurin inhibitor-induced endothelial dysfunction. CONCLUSIONS: Our study suggests that steroid-free immunosuppression is associated with a better fibrinolytic capacity in RTRs. This finding may contribute toward reducing the risk of cardiovascular events.

Adult↗