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Giuseppe Piccoli

Publications and source records attributed to Giuseppe Piccoli.

At least 19 recordsLinked to original sources

Efficacy of an educational programme for secondary school students on opinions on renal transplantation and organ donation: a randomized controlled trial.

CONTEXT: Organ shortage for transplantation is a crucial problem; educational interventions may increase donations and decrease opposition. OBJECTIVE: To test the efficacy of an educational programme on opinions on organ transplantation and kidney donation. DESIGN AND PARTICIPANTS: Cluster Randomized Controlled Trial: eight intervention and eight control schools were randomly selected from the 33 public schools that agreed to participate. Targets: students in the last 2 years of secondary school (17-18 years); seven schools per group completed the study. EDUCATIONAL PROGRAMME: INTERVENTION: first questionnaire (anonymous); 2 h lesson in each class; 2 h general session with patients and experts; second questionnaire. CONTROL: questionnaires. MAIN OUTCOME MEASURES: Differences between questionnaires (comparative analysis); interest; satisfaction with the programme; (cross-sectional analysis). RESULTS: 1776 first, 1467 second questionnaires were retrieved. Living kidney donation: at baseline 78.8% of students would donate a kidney to a relative/friend in need. The answers were unaffected by type of school but depended on sex (females more prone to donate, P<0.001); the answers did not change after the lessons. Cadaveric kidney donation: baseline opinions were mixed (intervention schools: 31.5% yes, 33.7% no, 34.8% uncertain), depending on type of school (classical-scientific high schools more positive than technical institutes, P<0.001), sex (males more prone to donate, P<0.001). Answers on living and cadaveric donation were correlated (P<0.001). The educational intervention increased favourable (31.5 to 42.9%) and uncertain (34.8 to 41.1%) opinions and decreased negative ones (33.7 to 16%) (P<0.001). CONCLUSIONS: Educational interventions are effective in increasing interest and improving opinions about cadaveric organ donation.

Adolescent↗

N-cadherin juxtamembrane domain modulates voltage-gated Ca2+ current via RhoA GTPase and Rho-associated kinase.

The juxtamembrane domain (JMD) of N-cadherin cytoplasmic tail is an important regulatory region of the clustering and adhesion activities of the protein. In addition, the JMD binds a diversity of proteins capable of modifying intracellular processes including cytoskeletal rearrangement mediated by Rho GTPases. These GTPases also function as regulators of voltage-activated calcium channels, which in turn modulate neuronal excitability. The present study was designed to determine whether there is a direct functional link, via Rho GTPase, between the N-cadherin JMD and these voltage-activated channels. It was found that the infusion of the soluble JMD into chick ciliary neurons causes a substantial decrease in the amplitude of the high-threshold voltage-activated (HVA) calcium current. The activation time is increased while the inactivation process is reduced, suggesting that the decreased current amplitude reflects a reduction in the number of channels available to open. This effect was reversed by inhibition of RhoA or its downstream effector, Rho-associated kinase (ROCK). Because ROCK determines the active state of myosin, these results suggest that the modulation of HVA by the JMD could be mediated by changes in the status of the actin-myosin cytoskeleton.

ADP Ribose Transferases↗

Patient referral is influenced by dialysis centre structure in the Diamant Alpin Dialysis cohort study.

BACKGROUND: Late referral (LR) to the nephrologist of patients with progressing chronic kidney disease (CKD) has numerous deleterious effects and is observed in many countries. The contributing factors associated with LR are controversial and poorly defined. We hypothesized that these factors might be better identified by analysing patients starting dialysis in three distinct European countries within the same area. METHOD: The referral and progression of kidney failure patterns were analysed with demographic, clinical and biological data in 279 non-selected consecutive patients starting dialysis in eight centres of three adjacent regions in France, Italy and Switzerland. RESULTS: Early referral (>6 months before the start of dialysis) was seen in 200 patients (71.6%), intermediate referral (1-6 months) in 42 (15.1%) and LR (<1 month) in 37 (13.3%). However inter-centre variations were between 2 and 19% for LR and 6-50% for combined late and intermediate referral. There were no differences at the national levels, but LR was more frequent in the large city centres than in the private or regional structures, with 31 out of 169 (18.3%), two out of 55 (5.4%) and four out of 55 (7.3%), respectively, of their patients (P<0.01). By multivariate analysis, it appears that, besides the presence of an active cancer and the CKD progression rate, the centre structure and the referring physician (primary care physicians and nephrologists are less responsible for LR than other medical specialists) play a significant role in the practice of LR. CONCLUSIONS: Within a dialysis cohort spread over adjacent regions of three countries, LR has the same global distribution pattern, indicating that different health and social security systems do not play a major role in inducing or preventing this practice. The contributing factors for LR that were identified are the type of the referring physician and the structure of the dialysis unit. Both factors are potential targets for an educational and collaborative approach.

Aged↗

Vascular access survival and morbidity on daily dialysis: a comparative analysis of home and limited care haemodialysis.

BACKGROUND: Concerns about vascular access failure may have limited the widespread use of daily haemodialysis (DHD). We assessed the incidence and type of vascular access complications during DHD and other schedules, both at home and on limited care haemodialysis. METHODS: All patients were treated in a limited care and home haemodialysis unit with a stable caregiver team (November 1998-November 2002). Vascular access failure, surgical treatment, angioplasty and declotting were studied alone or in combination by univariate and multivariate models. We analysed the effects of age, sex, comorbidity, previous vascular events, schedule, setting of treatment (home, limited care), dialysis follow-up, vascular access (native vs prosthetic, first vs subsequent) and setting of vascular access creation. 'Intention to treat' and 'per protocol' analyses were performed. RESULTS: In 2160 patient-months (home dialysis: DHD 400 months, non-DHD 655 months; limited care: DHD 208 months; non-DHD 897 months), 57 adverse events occurred (27 failures), in which 30 were at home (nine DHD) and 27 were in limited care (five DHD). The probability of remaining free from adverse events at 6 and 12 months was 89% and 80% on DHD and 79% and 76% on other schedules ('intention to treat'). Univariate analyses revealed a significant difference for the setting of the vascular access creation (lower risk of vascular access complications in our centre) and sex (male sex was protective). Logistic regression and Cox analyses confirmed the role for the setting of the vascular access creation. CONCLUSIONS: Although DHD did not appear as a risk factor for vascular access morbidity or failure at home or in a limited care centre setting, the setting of vascular access creation may influence its success.

Adult↗

Continuum of therapy in progressive renal diseases (from predialysis to transplantation): analysis of a new organizational model.

In the aging of Western populations, decreased mortality is counterbalanced by an increase in morbidity, particularly involving chronic diseases such as most renal diseases. The price of the successful care of chronic conditions, such as cardiovascular diseases or diabetes, is a continuous increase in new dialysis patients. However, the increased survival of patients on chronic renal replacement therapies poses new challenges to nephrologists and calls for new models of care. Since its split from internal medicine, nephrology has seen a progressive trend toward super specialization and the differentiation into at least 3 major branches (nephrology, dialysis, and transplantation), following a path common to several other fields of internal medicine. The success in the care of chronic patients is owed not only to a careful technical prescription, but also to the ability to teach self-care and attain compliance; this requires good medical practice and a sound patient-physician relationship. In this context, the usual models of care may fail to provide adequate coordination and, despite valuable single elements, could end up as an orchestra without a conductor. We propose an integrated model of care oriented to the type of patient (tested in our area especially for diabetic patients): the patient is followed-up by the same team from the first signs of renal disease to eventual dialysis or transplantation. This model offers an interesting alternative both for patients, who usually seek continuity of care, and for nephrologists who prefer a holistic and integrated patient-physician approach.

Adult↗

Lost to follow-up: the bottleneck of early referral to renal units?

BACKGROUND: Early referral is a major goal in chronic kidney diseases; however, loss to follow-up, potentially limiting its advantages, has never been studied. MATERIAL/METHODS: In order to assess the prevalence and causes of loss to follow-up, a telephone inquiry was performed in a renal outpatient unit, mainly dedicated to early referral of diabetic patients. Patients were considered to be in follow-up if there was at least one check-up in the period February 2001-February 2002, and lost to follow-up if the last check-up had occurred in the previous year. The reasons for loss to follow-up were related to typical clinical-biochemical parameters to define a "drop-out profile". RESULTS: 195 patients were on follow-up: median creatinine 1.4 mg/dL, age 64, 76.9% diabetics. 81 patients were lost to follow-up: creatinine 1.4 mg/dL, age 70, 73.8% diabetics. A telephone number was available in 87.6% of the cases; 25 were not found, 7 had died, 24 were non-compliant, 1 was bed-ridden, 12 had changed care unit, 2 had started dialysis. Renal care was shorter in those lost to follow-up; among the latter, serum creatinine and age were significantly lower in non-compliant patients. A logistic regression model confirmed the significance of lower serum creatinine at last check-up in non-compliant patients (p=0.018). CONCLUSIONS: Loss to follow-up is a problem in nephrology; lack of awareness probably causes the higher drop-out rate at lower creatinine levels. The initial period of care may be crucial for long-term compliance. Further studies are needed to tailor organizational and educational interventions.

Aged↗

Role of protein kinase C in light adaptation of molluscan microvillar photoreceptors.

The mechanisms by which Ca2+ regulates light adaptation in microvillar photoreceptors remain poorly understood. Protein kinase C (PKC) is a likely candidate, both because some sub-types are activated by Ca2+ and because of its association with the macromolecular 'light-transduction complex' in Drosophila. We investigated the possible role of PKC in the modulation of the light response in molluscan photoreceptors. Western blot analysis with isoform-specific antibodies revealed the presence of PKCalpha in retinal homogenates. Immunocytochemistry in isolated cell preparations confirmed PKCalpha localization in microvillar photoreceptors, preferentially confined to the light-sensing lobe. Light stimulation induced translocation of PKCalpha immunofluorescence to the photosensitive membrane, an effect that provides independent evidence for PKC activation by illumination; a similar outcome was observed after incubation with the phorbol ester PMA. Several chemically distinct activators of PKC, such as phorbol-12-myristate-13-acetate (PMA), (-)indolactam V and 1,2,-dioctanoyl-sn-glycerol (DOG) inhibited the light response of voltage-clamped microvillar photoreceptors, but were ineffective in ciliary photoreceptors, in which light does not activate the G(q)/PLC cascade, nor elevates intracellular Ca2+. Pharmacological inhibition of PKC antagonized the desensitization produced by adapting lights and also caused a small, but consistent enhancement of basal sensitivity. These results strongly support the involvement of PKC activation in the light-dependent regulation of response sensitivity. However, unlike adapting background light or elevation of [Ca2+]i, PKC activators did not speed up the photoresponse, nor did PKC inhibitors antagonize the accelerating effects of background adaptation, suggesting that modulation of photoresponse time course may involve a separate Ca2+-dependent signal.

Adaptation, Ocular↗

Patients on renal replacement therapy for 20 or more years: a clinical profile.

BACKGROUND: Long-term survivors are living evidence of the goals and limits of renal replacement therapy (RRT). METHODS: A cross-sectional study was performed on all cases (188 patients) with RRT follow-up >/=20 years in Piemonte, northern Italy (4 350 000 inhabitants, 22 dialysis centres). Study included revision of clinical charts and assessment of functional (Karnofsky scale, Ks) and nutritional status (subjective global assessment, SGA). According to treatment history, patients were sorted into three groups: group 1, 56 patients always on dialysis; group 2, 40 patients on dialysis with previous graft; group 3, 92 grafted patients. RESULTS: Age differed between group 1 and groups 2 and 3 (59.5+/-11.5 vs 51.5+/-7.9 and 51.0+/-9.0 years; P=0.001). Prevalence of comorbidity was higher in groups 1 and 2 (94.6% and 95%) compared with group 3 (81.5%), reflecting selection during follow-up. Twenty-two cases (11.7%) had no comorbidity; these patients were younger (44.3+/-8.5 years) and 17 out of 22 had a functioning graft. The most common comorbidities were vasculopathy (73.4%), bone disease (72.9%) and cardiopathy (33.5%). Severe visual impairment was a common problem (18%), with a higher prevalence in patients with cardiovascular comorbidity (32%). Severe depression was found in 13.3% of cases. Despite comorbidity, functional scores (Ks) were good (higher in group 3 (88.1+/-15) than in groups 1 and 2 (67.9+/-21.9 and 75.5+/-18, respectively); P=0.000) and 64% of patients were well nourished. The combination of cardiovascular comorbidity, bone disease and visual impairment may reflect the premature ageing of RRT patients. CONCLUSION: Despite the high prevalence of comorbidity, long-term follow-up may promote good clinical conditions at least in some patients, highlighting the therapeutic potentials of dialysis in an era of reconsideration of open acceptance of RRT.

Adult↗

Flexibility as an implementation strategy for a daily dialysis program.

BACKGROUND: Daily hemodialysis (DHD) is an interesting dialysis option, experienced worldwide by only a few hundred patients, because of clinical and logistic limitations. This study describes the main clinical and implementation results of a flexible policy applied in starting a DHD program. METHODS: The setting is the University Nephrology Center of Turin, Italy (approximately 150 hemodialysis and 50 peritoneal dialysis (PD) patients) where in November 1998 a short daily DHD program was started. Outcome measures were logistical (enrollment rate, indications and drop-outs) and clinical (dialysis efficiency, metabolic control, hypertension and anemia control). RESULTS: 25 patients experienced DHD, 16 (11% of the hemodialysis pool) were on DHD in November 2001; overall the DHD follow-up was 409.1 months (median 18, range 0.7-36 months). Flexibility was applied to schedules (patients modulated dialysis time and could switch to 3-4 sessions/wk); treatment setting (home: 11 patients, limited care center: 13; alternate settings: one); clinical selection (23/25 patients with comorbidity). Main reasons for choice were poor tolerance of previous schedule and the search for "best" treatment. Five patients dropped out (work reasons), one died on DHD and three were grafted. As compared to baseline, dialysis efficiency increased (EKRc pre-DHD 14.5 +/- 2.1 mL/min; 17.4 +/- 2.8 mL/min and 17.7 +/- 3.5 mL/min at 1-6 months; p<0.000). Despite the potentially confusing effect of comorbidity, the main clinical data improved. CONCLUSIONS: A flexible approach allowed development of DHD in approximately 11% of hemodialysis patients, with promising clinical results, despite frequent comorbidity.

Adult↗

The Diamant Alpin Dialysis cohort study: clinico-biological characteristics and cardiovascular genetic risk profile of incident patients.

BACKGROUND: Clinical and therapeutic characteristics of chronic dialysis patients vary widely at national and/or regional levels. Their increased cardiovascular (CV) mortality is not explained by traditional cardiovascular disease (CVD) risk factors only. Therefore, this study aimed to investigate and compare the characteristics of patients starting dialysis in a homogeneous Alpin region and possibly to identify new biological parameters (phenotypes or genotypes), which eould be responsible for the increased CVD seen in end-stage renal disease (ESRD) patients. METHODS: A cohort of 279 non-selected consecutive patients entering a dialysis program was prospectively investigated in eight centers of three adjacent regions in France, Italy and Switzerland. In addition to the usual demographic, clinical and biological data, we analyzed at study entry the blood levels of homocysteine, lipoprotein(a) (Lp(a)) and antioxidized low density lipoprotein (LDL) antibodies, vitamin B12 status, Lp(a) and haptoglobin phenotypes, methylenetetrahydrofolate reductase (MTHFR), angiotensin-converting enzyme (ACE), allele epsilon E4 of apolipoprotein (ApoE4) and plasminogen activator inhibitor-1 (PAI-1) genetic polymorphism. RESULTS: At entry, 90.3% of patients were hypertensive, 30% had type 2 diabetes mellitus and 17.6% were current smokers; 42% of patients had already experienced at least one CV event: peripheral artery disease (26% of the cohort), coronary artery disease (22%) or ischemic cerebro-vascular disease (16%). Forty-two patients had had > or =2 CV events or documented atherosclerotic localizations. Anemia was not optimally treated: mean hemoglobin (Hb) was at 97.7 g/L and, while overall 62% of patients received erythropoietin (EPO) prior to dialysis, large national differences were observed. Compared to the reference population, ESRD patients exhibited increased homocysteinemia, Lp(a) levels and ApoE4 allele prevalence. Conversely, the distribution of Lp(a) phenotype, MTHFR TT, ACE DD and PAI-1 4G/4G was equivalent to that of the reference population. In addition, none of the analyzed phenotypical or genotypical parameters, except for the haptoglobin 2.2 phenotype, could be associated with the existence of a previous adverse CV event. CONCLUSIONS: (1) The clinical characteristics of the ESRD patients entering dialysis in our region were comparable to the currently observed dialysis populations in most European countries with the deleterious role of advancing age, diabetes, previous CVD, smoking and hypertension evident (2). Except for anemia therapy, there were no regional or national differences observed at dialysis start. (3) An analysis of the phenotypic and genotypic CV risk factors demonstrated differences with the reference population only for hyperhomocysteinemia, Lp(a) and ApoE4 allele prevalence, with no notable differences among the participating centers.

Adult↗

Home hemodialysis à la carte: a tailormade program (1998-2003).

BACKGROUND: There are good epidemiological (increased numbers of dialysis patients), economical (renal replacement therapy (RRT) costs) and clinical reasons (new highly efficient schedules) to reconsider the choice of home hemodialysis (HD). STUDY AIM: Analysis of the results and costs of a flexible, tailormade home dialysis program (1998-2003). SETTING: Home HD facility of the University of Turin-Italy. METHODS: Results were analyzed in terms of feasibility (enrolment rate, logistical problems--the two usual caregivers performed a retrospective analysis of the clinical records; production costs, assessed with a logic bottom-up technique). Since the main program feature was the tailoring of dialysis to the patient, kinetic data were analyzed to control the efficiency of the chosen schedules. RESULTS: In 1998-2003 (54 months), 31 patients joined the home HD program (six patients were already being treated), while another 12 patients were treated in the training area and trained for an ongoing self-care program; mean age was 47.1 +/- 12.8 yrs; 35/49 patients had clinical comorbidities. During the study, four patients died, 10 were grafted, and six patients dropped out or were transferred. In March 2003, 23 patients were at home/in training and six were being treated in the training area: 11 patients were on a conventional schedule, four on daily dialysis, 12 on other schedules (two patients non-resident in the Piedmont region were not considered). Dialysis efficiency reached the target (EKRc > 11 mL/min) in all but four patients (schedules with more frequent sessions were planned for these patients). Costs were comparable to limited care HD (daily: 96.5 euros/session at home, 98.76 euros/session in the center; conventional: 133.48 euros/session at home, 131.25 euros/session in the center). CONCLUSION: A tailored, flexible policy can help to revive a home HD program.

Adult↗