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L Esposito

Publications and source records attributed to L Esposito.

At least 19 recordsLinked to original sources
PubMed2006

Aquaporin-2 excretion and renal function during the 1st week of life in preterm newborn infants.

In many preterm infants, a characteristic pattern of fluid and electrolyte homeostasis occurs during the 1st week of life, consisting of three phases: prediuretic, diuretic, and postdiuretic. In this study, we evaluated the possible role of aquaporin-2 (AQP2) in renal concentrating ability and correlated it with other markers of the renal function in healthy preterm infants. Daily urine and spot blood samples were collected from 9 healthy preterm (32 +/- 1 weeks) infants at postnatal ages 1, 3, and 7 days. Urine and serum osmolality, creatinine, electrolytes, and AQP2 excretion were measured. All infants showed a significant (about 7%) weight loss on day 3 associated with a more than threefold increase in urine output without a significant change in fluid intake (diuretic phase). The creatinine clearance increased on day 3, indicating an increase in glomerular filtration rate. Interestingly, on day 3, the level of total excreted AQP2 (pmol/h) was significantly higher when compared to day 1 and day 7, and the same tendency was observed for urine osmolality. To conclude, the observed increase in urine osmolality and creatinine clearance during the diuretic phase, paralleled by an increase in total AQP2 excretion, suggests that AQP2 can contribute to the urinary concentrating ability early in postnatal life.

Aquaporin 2↗
PubMed2006

Enceladus' water vapor plume.

The Cassini spacecraft flew close to Saturn's small moon Enceladus three times in 2005. Cassini's UltraViolet Imaging Spectrograph observed stellar occultations on two flybys and confirmed the existence, composition, and regionally confined nature of a water vapor plume in the south polar region of Enceladus. This plume provides an adequate amount of water to resupply losses from Saturn's E ring and to be the dominant source of the neutral OH and atomic oxygen that fill the Saturnian system.

Atmosphere↗
PubMed2006

Predictive factors for anemia within the first year after orthotopic liver transplantation.

We sought to determine the prevalence and predictive factors for posttransplant anemia within the first year after orthotopic liver transplant (OLT) among 97 consecutive patients. Anemia was defined at months 6 and 12 according to the WHO criteria, that is, a hemoglobin (Hb) level of <12 g/dL for women and <13 g/dL for men. Immunosuppression relied on tacrolimus and steroids, with or without mycophenolate mofetil. Anemia was present in 64.5%, 50%, and 52.8% of patients pre-OLT versus 6 and 12. Thirty-three percent (month 6) and 30.3% (month 12) of anemic patients received recombinant erythropoietin therapy. A multivariate analysis revealed that the independent predictive factors for anemia at month 6 were mean corpuscular volume (<85 fL) at day 7, daily steroid dosage (<0.3 mg/kg), serum creatinine (>130 mumol/L), and Hb level (<11 g/dL) at month 1. Independent predictive factors for anemia at month 12 were daily steroid dosage at month 1 (<0.3 mg/kg), hematocrit at month 1 (<33%), red blood cell count at month 6 (<3.75 T/L), daily dosage at month 1 of cyclosporine or tacrolimus, and etiology of end-stage liver disease other than alcohol abuse. We concluded that anemia was highly prevalent within the first year of post-OLT. This observation deserves further investigation and appropriate treatment.

Anemia↗
PubMed2006

Predictive factors for cytomegalovirus infection after orthotopic liver transplantation using an ultrasensitive polymerase chain reaction assay.

The predictive factors for cytomegalovirus (CMV) infection in de novo liver transplant patients were determined at 3 months posttransplantation. We included all consecutive patients except those who died or who had lost their graft within 1 month posttransplant. We recorded both donor (D) and recipient (R) data. Immunosuppression utilized tacrolimus, steroids, with or without mycophenolate mofetil, and/or induction therapy with anti-CD25 monoclonal antibodies. CMV prophylaxis was administered only to those at high risk of CMV infection, namely, D+/R- patients. These cases received intravenous ganciclovir at 500 mg/d for the first 2 weeks followed by oral ganciclovir at 500 mg for the following 3 months. The median time to CMV infection was 1 month. The significant predictive factors for CMV infection were D/R CMV status, (P = .002): D+/R+ versus other patients (P = .01), D-/R- versus other patients (P = .002), D+ versus D- (P = .009). In addition infection was associated with the original liver disease (hepatitis C virus infection or alcohol-related cirrhosis; P = .03), R+ vs. R- (P = .03), donor age (<45 or >45 years; P = .01), lymphocyte count at M2 (< or >1300/mm(3); P = .02), hemoglobin levels at 1 and 3 months, and platelet and white blood cell counts at day 7. The independent predictive factors were recipient CMV sero-status (R+ vs R-; odds ratio = 10.2), donor age >45 years (odds ratio = 11.4) and lymphocyte count at M2 <1300/mm(3) (odds ratio = 7.33). This study showed that the major factors associated with CMV infection were recipient CMV status, donor age, and lymphocyte count.

Base Sequence↗
PubMed2006

Monitoring HCMV infection with quantitative real-time PCR in HCMV-positive orthotopic liver transplant recipients, and predictive factors for treatment of the first episode of HCMV viremia.

We evaluated the relevance of human cytomegalovirus (HCMV) monitoring with quantitative real-time polymerase chain reaction in 42 consecutive HCMV positive liver transplant patients, and we analyzed the factors that determined the treatment of the first episode of HCMV DNAemia. No patients received anti-HCMV prophylaxis. HCMV infection monitoring was assessed every 2 weeks until day 90 and thereafter at every 3 to 4 weeks until day 180. HCMV infection was detected among 27 patients (64%, ie, 92/380 samples). Of these, 12 had their first HCMV DNAemia treated with IV gancyclovir (group I), whereas the other 15 patients were not treated (group II). Immunosuppressive treatment was not modified in cases of HCMV DNAemia. The median time between transplantation to the first CMV DNAemia was 37 days in group I and 52 days in group II (NS). Median HCMV viral load, whatever the treatment group and whatever the time of DNAemia, was 3 log copies/mL (0.48 to 5.80). Median HCMV viral load of the first positive DNAemia was 3.45 log copies/mL (1.69 to 5.80) in group I and 2.70 log copies/mL (1.15 to 3.94) in group II (P = .01). Even though liver enzymes were increased in almost all patients presenting with HCMV infection, comparison of liver-enzyme levels and hematological parameters between the two groups at first HCMV viremia showed that alkaline phosphatase levels were significantly higher (P = .0011) and hemoglobin levels were significantly lower in group I patients (P = .0443). The only factor that predicted treatment for the first episode of HCMV DNAemia was an alkaline phosphatase level >150 UI/mL at the time of the first HCMV reactivation [odds ratio 20 (1.96 to 203.3); P = .01].

Adrenal Cortex Hormones↗
PubMed2006

Rituximab therapy for mixed cryoglobulinemia in seven renal transplant patients.

Systemic B-cell depletion and clinical remission of the systemic effects of cryoglobulins have been achieved in hepatitis C virus-positive immunocompetent patients with rituximab, a human/mouse chimeric monoclonal antibody that specifically reacts with the CD20 antigen. Thus, this provides a rationale for the use of rituximab for type III cryoglobulin-related graft dysfunction in renal-transplant patients. Seven patients, of whom five were hepatitis C positive, developed renal function impairment long after transplantation, as well as de novo nephrotic syndrome (n = 5), severe hypertension (n = 5), nephritic syndrome (n = 1), and increased serum creatinine (n = 1). This type III cryoglobulinemia was associated with membranoproliferative glomerulonephritis and with thrombi within the glomeruli in one case. In addition to their baseline standard immunosuppressive medications, the patients were given weekly rituximab infusions: 375 mg/m(2) for 2 weeks in four cases, for 3 weeks in one case, and for 4 weeks in two cases. This treatment resulted in a dramatic improvement in all renal parameters, particularly a sustained remission of nephrotic syndrome in three cases, the disappearance of nephritic syndrome in one patient, and improved nephrotic syndrome in two cases, as well as a sustained clearance of cryoglobulins in six cases. However, it also resulted in severe infectious complications in two cases. We concluded that rituximab therapy is effective in cryoglobulin-related renal dysfunction in renal transplant patients but, due to chronic immunosuppression, this may be achieved at the expense of infectious complications.

Antibodies, Monoclonal↗
PubMed2006

Acute renal failure following liver transplantation with induction therapy.

AIMS: To identify the predictive factors for acute renal failure (ARF) in a retrospective study of 100 orthotopic liver transplantations (OLT) performed in 94 patients between 2000 and 2003. METHODS: Acute renal failure (ARF) was defined using the RIFLE criteria, i.e. injury when creatinine doubles or GFR halves, and failure when creatinine trebles or GFR decreases by > 75%. Patients on dialysis pre OLT (n = 3) were excluded from the study. Immunosuppression included steroids, calcineurin inhibitors (CNIs), with (n = 32) or without mycophenolate mofetil. A total of 85% of patients also received induction therapy with antithymocyte globulins (29%) or anti-CD25 monoclonal antibodies (56%). RESULTS: 39 patients (41.5%) and 21 (22.3%) patients developed injury, and failure, respectively. Of these, 10 (10.6%) underwent dialysis. Univariate analysis revealed that acute renal dysfunction with a RIFLE score > or = 3 was significantly associated with a pre-operative serum creatinine level of > 100 micromol/l, pre-operative creatinine clearance of < 75 ml/mn, need for a transfusion (> 10 red packed units), post-operative diuresis of < 100 ml/h, use of vasopressive drugs, times to aspartate (AST) and alanine (ALT) aminotransferase peaks of > 20 and > 24 hours, respectively, relaparotomy, CNIs transient discontinuation, and the use of lower daily dosage of CNIs at post-OLT Days 3, 5, 7 and 15. In multivariate analysis, failure was significantly associated with time to AST peak (> 20 h) (OR 6.35 (1.2 - 33.6), p = 0.029), post-operative diuresis (< 100 ml/h) (OR 9.8 (2.03 47.3), p = 0.004), post-operative use of vasopressive drugs (OR 9.91 (2.02 - 48.7), p = 0.004), and transient CNIs withdrawal (OR 51.08 (7.58-344.1), p < 0.0001). Finally, the occurrence of ARF was significantly associated with an increased number of days on mechanical ventilation, on stay-in intensive care unit (ICU), and on overall hospitalization time. CONCLUSION: ARF is quite common after OLT and significantly increases the post-operative time at the hospital, thereby increasing the OLT cost. Its independent predictive factors are mainly related to perioperative events.

Acute Kidney Injury↗
PubMed2005

Predictive factors of postrenal transplant anemia.

OBJECTIVE: The aim of our study was to identify independent factors that might predict anemia at 6 months' (M6) and 12 (M12) months' posttransplantation. Postrenal transplant anemia was defined as a hemoglobin (Hb) level below 13 g/dL for men, and below 12 g/dL for women. We included 99 renal transplants performed in our department in 2001, for whom the graft was still functioning at 1 year. RESULTS: Anemia was observed in 78%, 35.5%, and 25% on day (D) 0, and at M6, and M12, respectively. Iron deficiency was observed in 14% of patients at D0, and 13% at M12. During the postoperative period, 59.8% of patients received at least one blood transfusion, whereas 37% of patients were prescribed recombinant erythropoietin (rEpo) therapy within the first few months posttransplantation. By multivariate analysis the independent predictive factors for anemia at M6 were rEpo therapy at D0, initial nephropathy, posttransplantation rEpo therapy, hematocrit at M3, platelets at D7 and sirolimus therapy. The independent predictive factors for anemia at M12 were rEpo therapy at D0 and platelets at D7, delayed graft function (DGF), serum creatinine, and creatinine clearance at M12, and Hb level at M6 were also checked. CONCLUSION: The prevalence of anemia is 25% at M12; DGF, renal function at M12, and anemia at M6 were independent risk factors of anemia at M12.

Adult↗
PubMed2005

Long-term evolution of lymphocytes subsets after induction therapy based on continuous versus discontinuous administration of anti-thymocyte globulins in renal-transplant patients.

UNLABELLED: The aim of our retrospective study was to assess the long-term evolution of lymphocyte subsets after two modes of administration of anti-thymocyte globulin (ATG) after renal transplantation. METHODS: Before 1993, patients (group I, n = 93) received fixed doses of RATG (1 mg/kg per day) for 8 consecutive days. Thereafter, RATG was either continued at the same dose for 15 days, in cases of delayed graft function, or was infused every other day at the same dose until the serum creatinine level became <150 micromol/L. After 1993, patients (group II, n = 66) received RATG at full dose (1 mg/kg per day) during the first 3 days and, thereafter, doses were adapted to target a CD2 T-cell count <50/mm3. RATG cumulative dose was significantly higher among group I than group II (9.7 +/- 4.5 versus 7.4 +/- 3.2 mg/kg, P = .0002). RESULTS: In both groups, total lymphocyte and T lymphocyte subset (CD4, CD8, CD2, CD3) counts decreased significantly during the first month after transplantation, increasing slowly between the first month and the third year posttransplantation. Thereafter it rose rapidly, which was greater in group II. At last follow up, total lymphocyte, T lymphocyte subsets and NK cell counts were similar to those observed before transplantation. At all monitoring times, T lymphocyte, B lymphocyte, and NK cell counts were similar in both group, except for the total lymphocyte count at 6 months and CD4 T lymphocyte count at 1 year, which were significantly higher in group II compared to group I. CONCLUSION: Induction therapy based on continuous or discontinuous administration of ATG is associated with profound depletion of T, B, and NK cells during the first 3 years, followed by a progressive reconstitution of the lymphocyte pool after 5 years.

Antigens, CD↗
PubMed2005

Comparison of induction based on continuous vs discontinuous administration of antithymocyte globulins in renal transplant patients: efficacy and long-term safety.

UNLABELLED: This retrospective study sought to compare two modes of administration of antithymocyte globulin (RATG) after renal transplantation. METHODS: Before 1993, group I patients (n = 93) received fixed doses of RATG (1 mg/kg per day) for 8 consecutive days. Thereafter, RATG was either continued at the same dose for 15 days, in cases of delayed graft function, or was infused every other day at the same dose until serum creatinine level became <150 micromol/L. After 1993, group II patients (n = 66) received RATG at full dose (1 mg/kg per day) during the first 3 days and thereafter the doses were adjusted to target a CD2 T-cell count <50/mm3. Both groups received steroids, azathioprine, and cyclosporine. The mean follow-up after transplantation was 117 +/- 31 months in group I and 93 +/- 19 months in group II. RESULTS: The RATG cumulative dose and consequently cost were significantly higher among group I than group II patients. Long-term patient and graft survival were similar in both groups. The rate of acute graft-rejection episodes was significantly higher among group I than group II patients. At 7 years posttransplantation, the serum creatinine level and creatinine clearance were similar in the two groups. The rate of cytomegalovirus infection, as well as the cumulative incidence of severe infections and cancers were also similar in both groups. Among the cancers, skin neoplasms represented 30% in group I and 26% in group II (P = ns). CONCLUSION: Adjusting RATG doses according to the CD2 lymphocyte count is safe, and a less expensive than using full doses.

Adult↗
PubMed2005

Impact of excess weight and estrogen receptor gene polymorphisms on clinical course of homozygous beta thalassemia.

In homozygous beta thalassemic patients we examined the role played by the interaction of ER gene polymorphisms with adverse environmental factors. A total of 108 homozygous beta thalassemic patients, 60 prepubertal mean age 9,5 +/- 3,7 years (27 M, 33 F) and 48 pubertal mean age 22,2 +/- 5,4 years (21 M, 27 F), regularly treated with red cell transfusion and iron chelation therapy were segregated on the basis of their XbaI and PvuII ER gene polymorphisms. Body mass index (BMI), lipidic pattern and blood pressure values were evaluated in each group. No significant differences were observed between patients segregated by their PvuII ER genotypes. Prepubertal and pubertal patients of both sexes lacking XbaI site showed BMI, HDL, LDL cholesterol significantly different than the other patients. In addition, triglyceride levels and blood pressure values were significantly higher in pubertal patients of both sexes lacking XbaI site than in other patients. ER XbaI polymorphism appear to influence nutritional factors, metabolic status and blood pressure and could be considered additional risk factors for later cardiac involvement in beta thalassemic patients.

Adolescent↗
PubMed2005

Side effects of corticosteroid therapy in children with chronic idiopathic thrombocytopenic purpura.

In 29 symptomatic children of both sexes with chronic idiopathic thrombocytopenic purpura (CITP) with platelet counts < or = 30,000/mm3, of mean age 7.2 +/- 1.3 years, the side effects of long-term glucocorticoid therapy were evaluated. Patients were divided into three groups based on the different glucocorticoid protocols they were receiving. Baseline measurements (t0) of height (H) as standard deviation score (SDS), body mass index (BMI) as kg/m2 and bone mineral density (BMD) at the femoral neck (FBMD) and lumbar spine L2-L4 (LBMD) by a dual energy X-ray absorption technique, expressed as Z score, with follow-up measurements at 1 (t1) and 2 (t2) years were assessed. Group I patients (10 pts) treated with oral prednisone (2 mg/kg/die-for one month for 2 cycles) showed significantly different HSDS, BMI, FBMD and LBMD at t1 and t2 (P < 0.005) than other groups treated respectively with pulsed high doses of dexamethasone (24 mg/m2 over 4 days/months for 6 cycles) and methylprednisolone (9 mg/kg/die for 5 days for 3-4 months). These findings suggest that pulsed high doses of glucocorticoid lead to fewer side effects than oral prednisone therapy.

Absorptiometry, Photon↗
PubMed2002

Volumetric determination of the wear of ceramics for hip joints.

Osteolysis relating to the reaction cascade to wear debris is the main cause of the failure of arthroprostheses. New materials are still under development to minimise the wear of joints and to improve in this way the performance of total joint replacements. Testing the wear performance of very low wear materials is a rather sophisticated technique. Currently, the worn volume is calculated from the weight variations of the sample, observed from wear testing. This method may be limited especially when very low weight differences are to be evaluated on high hardness, high-density materials like CoCr alloys or ceramics like alumina or zirconia. In the present work, the tribological behaviour of ceramic biomaterials like alumina, Y-TZP and alumina-zirconia composites was evaluated by a pin-on-disc apparatus under different testing conditions. The worn volume was calculated by the use of 3-D (three-dimensional) optical profilometry data. Comparison between 3-D optical profilometry and gravimetric wear data shows the better accuracy of the profilometric method in the determination of wear rate in the range of 10(-7) mm3 (mN(-1)) or lower.

Biomechanical Phenomena↗
PubMed2001

Neuroprotection afforded by some hindered phenols and alpha-tocopherol in guinea-pig detrusor strips subjected to anoxia-glucopenia and reperfusion-like conditions.

2-t-butyl-4-methoxyphenol (BHA), 3,5-di-t-butyl-hydroxyanisole (DTBHA), 2,6-diisopropylphenol (propofol), alpha-tocopherol (alpha-TOC) and two newly synthesised analogues of BHA, namely 1-O-(4-hydroxy-3-t-butyl)phenyl-2,3,4,6-tetra-O-acetyl-beta-D-glucopyranose (beta-TAG) and 1-O-(4-hydroxy-3-t-butyl)phenyl-beta-D-glucopyranose (beta-GLU), were tested for their capability to protect the intrinsic nerves of guinea-pig urinary bladder from damage due to anoxia-glucopenia and re-exposure to glucose and O2. Guinea-pig detrusor strips were mounted for tension recording in small organ baths, superfused with warmed Krebs solution and the nerves stimulated electrically either under control or ischaemia-like (anoxia-glucopenia) and reperfusion-like conditions (normal medium re-superfusion). The Ca2+ antagonist activity of the compounds was assessed by their effect on the contraction of detrusor strips induced by 60 mM K+ Krebs solution in the presence of either 0.5 mM or 5 mM Ca2+. The antioxidant activity was illustrated by the ability of the compounds to scavenge peroxyl radicals generated by linoleic acid oxidation. All the compounds, except beta-GLU and alpha-TOC, inhibited in a concentration-dependent manner K+-induced contractions of detrusor muscles, the inhibition being inversely related to the Ca2+ concentration of the perfusion solution; moreover, they exhibited a marked antiperoxidant activity with pIC50 values decreasing in the order: DTBHA > alpha-TOC > BHA > beta-TAG > propofol > beta-GLU. alpha-TOC, BHA, DTBHA and beta-TAG improved significantly the response of the strips to electrical field stimulation either during the anoxia-glucopenia phase or thereafter when recovering during reperfusion, as compared to untreated tissues. The neuroprotection afforded by the phenol derivatives as well as by alpha-TOC was positively correlated to their antioxidant activity, but not to their Ca2+ antagonist activity.

Analysis of Variance↗
PubMed2001

Isolation and morphological characterisation of UHMWPE wear debris generated in vitro.

Wear tests are generally carried out on materials used in prosthetic hip implants, in order to obtain a better understanding of the tribological processes involved and improve the quality control of joint prostheses, directed towards reducing the risk of implant failure of innovative prostheses. Ceramic femoral heads of mixed alumina-zirconia oxides as well as zirconia and alumina single oxide heads were tested against UHMWPE acetabular cups in a hip joint simulator. Polyethylene cups and ceramic femoral heads were mounted in a simulator apparatus moving according to a sinusoidal function, under load and in the presence of bovine calf serum as lubricant. Wear particles were isolated from the bovine calf serum collected during the wear tests. An easy to follow method was used to separate the wear particles from the lubricant. Chemical digestive methods were used to separate the wear particles from the lubricant and the isolated particles were studied using scanning electron microscopy. The morphologies of the polyethylene debris showed considerable differences, both in size and shape of the particles, as a function of the coupled head material.

Animals↗
PubMed2001

Haplotype tagging for the identification of common disease genes.

Genome-wide linkage disequilibrium (LD) mapping of common disease genes could be more powerful than linkage analysis if the appropriate density of polymorphic markers were known and if the genotyping effort and cost of producing such an LD map could be reduced. Although different metrics that measure the extent of LD have been evaluated, even the most recent studies have not placed significant emphasis on the most informative and cost-effective method of LD mapping-that based on haplotypes. We have scanned 135 kb of DNA from nine genes, genotyped 122 single-nucleotide polymorphisms (SNPs; approximately 184,000 genotypes) and determined the common haplotypes in a minimum of 384 European individuals for each gene. Here we show how knowledge of the common haplotypes and the SNPs that tag them can be used to (i) explain the often complex patterns of LD between adjacent markers, (ii) reduce genotyping significantly (in this case from 122 to 34 SNPs), (iii) scan the common variation of a gene sensitively and comprehensively and (iv) provide key fine-mapping data within regions of strong LD. Our results also indicate that, at least for the genes studied here, the current version of dbSNP would have been of limited utility for LD mapping because many common haplotypes could not be defined. A directed re-sequencing effort of the approximately 10% of the genome in or near genes in the major ethnic groups would aid the systematic evaluation of the common variant model of common disease.

Base Sequence↗