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R Boero

Publications and source records attributed to R Boero.

At least 19 recordsLinked to original sources

HLA-B35 frequency variations correlate with malaria infection in Sardinia.

The hypothesis of a possible selective role of malaria in HLA allele frequency variations was investigated in Sardinia by typing completely 1,039 individuals for HLA: 536 from six lowland villages exposed to malaria until 1948, and 503 from six highland villages with no history of malaria. Another 1,928 individuals from 136 villages scattered all over the island were studied to establish if the HLA allele frequencies among villages correlated with the malaria incidence and/or altitude above sea level. Only the HLA-B35 allele yielded significantly higher frequencies in the lowland versus the highland villages (P<1 x 10(-5)). The observed B35 variance was 9.5 times higher than expected in the absence of selection, showing an adaptive origin. The highly significant positive correlation found between HLA-B35 frequency and malaria in 136 villages suggests that malaria has been the selective factor for HLA-B35 in Sardinia.

Alleles

Myths and reality concerning hypertension in peritoneal dialysis patients: results of a multicenter study.

OBJECTIVES: To evaluate the prevalence of hypertension, the average blood pressure level, the 24 h blood pressure profile, and the efficacy of antihypertensive therapy for a large population of peritoneal dialysis patients.DESIGN: A cross-sectional, observational multicenter study. METHODS: From 504 peritoneal dialysis patients (18% of the Italian peritoneal dialysis population) involved in a multicenter observational study, we selected 414 who had undergone successful ambulatory blood pressure monitoring (i.e. no hours with data absent, >/= 75% successful readings and monitoring duration >/= 24 h). Office blood pressure measurements and ambulatory blood pressure monitoring were performed for each patient on the same day with a standard mercury sphygmomanometer and a SpaceLabs 90207 device, respectively.RESULTS: According to World Health Organization/International Society of Hypertension criteria, 44 peritoneal dialysis patients (10.6%) were normotensive and 370 patients (89.4%) were hypertensive, 304 (82.1%) of whom were being administered antihypertensive therapy. Daytime systolic and diastolic blood pressures were both significantly lower than office systolic and diastolic blood pressures (140.7 +/- 19.7/72.1 +/-11.1 versus 148.3 +/- 23.6/85.6 +/- 12 mmHg; P < 0.001). The difference between office blood pressure and daytime blood pressure was significantly correlated to office blood pressure (P < 0.001 for systolic and P < 0.001 for diastolic). The diurnal blood pressure rhythm evaluated by visual inspection of hourly mean plots was not influenced by sex, age, antihypertensive treatment, and peritoneal dialysis modality. Systolic and diastolic blood pressures exhibited a day-night mean decreases of 8.6 +/- 11.7 and 7.7 +/- 6.9 mmHg, respectively, and daytime blood pressure values were significantly higher than night-time ones (P < 0.001). Two hundred and twenty patients (53.1%) were nondippers according to O'Brien's criteria, 247 patients (59.7%) were nondippers according to Verdecchia's criteria, and 269 patients (65.0%) were nondippers according to Staessen's criteria. Only 39 patients (9.4%) had a reversed circadian rhythm. The day-night differences of systolic and diastolic blood pressures were in a unimodal distribution. Among hypertensive patients not being administered antihypertensive therapy, only six patients ( five women and one man) had white-coat hypertension. Among hypertensive patients being administered antihypertensive therapy, 235 patients (77.3%) had 24 h blood pressure loads > 30%.CONCLUSION: There is a high prevalence of hypertension among peritoneal dialysis patients. White-coat hypertension is very rare in this population. Despite the extensive use of antihypertensive therapy, control of blood pressure is maintained in a large number of our peritoneal dialysis patients. Any classification of patients into dipers and nondippers must be interpreted cautiously.

Journal Article

[Vascular access for chronic hemodialysis: current status and new directions in the Piedmont].

Long survival on dialysis and wide admissions of very old and high risk patients, have focused attention to the problem of vascular access in uremic patients. The situation is critical in the USA, where PTFE/bovine grafts are utilized in about 75% of the cases. conversely, AV fistulas are the main type of access in Piedmont, where their use approaches 90% of the cases, Cimino-Brescia fistulas account for 58% of vascular accesses versus 25% and 9% of proximal AV fistulas and PTFE/bovine grafts, respectively. However, the latter progressively increase as age and time on dialysis increase. Snuff box fistulas are used only for 3% of the cases and this figure is steadily decreasing. In the meanwhile basilic vein superficializations, even if limited in numbers (1%), provided in some centres satisfactory results in term of survival and function. However, the type of access that deserved in the last few years the highest interest is the internal jugular vein cannulation (Canaud/Tesio catheter). In a preliminary series of 51 cannulations in 47 patients, this vascular access was permanent in 28 cases. A possible future routine utilization of jugular vein catheters is advisable in cases where a waiting period (up to a few months) is requested to allow a new fistula to mature or to maintain an empty abdomen in a patient temporarily withdrawn from peritoneal dialysis. Due to the heavy engagement for catheter maintenance and the high number of removals for systemic (9.8%) or skin exit infections (13.7%), a longer stay of indwelling catheters, although actually safe, should be limited to selected cases.

Adult

Correlations between bone histopathology and serum biochemistry in uremic patients on chronic hemodialysis.

To define which noninvasive investigations are of value in predicting bone histology, we analyzed transiliac bone specimens (66 biopsies, 14 autopsies) from 80 uremic patients on chronic dialysis. Results were compared with values of different measurements of parathyroid hormone (PTH), alkaline phosphatase (APH), osteocalcin, calcitonin, baseline and post-deferroxamine (DFO) aluminium (Al),--beta 2 microglobulin, ferritin and bone mineral density. Among histomorphometric parameters, woven osteoid, active osteoblastic surface and resorption surface showed the best correlations with dynamic and biochemical marks of active bone metabolism. Among biochemical parameters, intact PTH and APH were better related to histomorphometric and dynamic bone parameters than other PTH measurements as well as osteocalcin, while calcitonin was related to no parameters. Stainable Al alone, and not total bone Al content was related to bone histology. Baseline Al was related to lamellar osteoid, while post-DFO Al was related to stainable Al. beta 2 microglobulin was positively related to active osteoid surface and ferritin was inversely related to the mineral apposition rate, while bone mineral density was related only to total bone volume. We conclude that, though definite diagnosis requires the use of histological methods, few simple biochemical parameters may offer insight to the bone metabolic status, useful to the physician in day to day clinical practice.

Absorptiometry, Photon

HLA haplotypes and class II molecular alleles in Sardinian and Italian patients with pemphigus vulgaris.

HLA class II antigens and DRB1, DQA1, DQB1 alleles were studied in 16 Italian and in 16 Sardinian patients with pemphigus vulgaris (PV). In the last group the complete HLA A-DQ haplotypes, including the complotypes, were defined by family studies. As in other populations, two PV susceptibility haplotypes were found: HLA-DRB1*0402, DQA1*0301, DQB1*0302 and HLA-DRB1*1401, DQA1*0104, DQB1*0503. The first haplotype was largely prevalent in the Sardinian patients and was a part of the extended haplotype HLA-A2, Cw4, B35, S31, DR4, DQ8. The strength of the allele associations to PV is in agreement with the view that the main PV susceptibility genes are the DRB1*0402 and DQB1*0503 alleles. A genetic resistance to PV seems to be conferred by the HLA-DR3, DQ2 haplotype in the Sardinian population.

Alleles

HCV viremia in hemodialysis patients: detection by a DNA enzyme immunoassay for amplified HCV sequences.

The aim of this study was the detection of HCV viremia in both anti-HCV antibody positive and negative hemodialysis patients. Sera from 75 patients on extracorporeal blood purification in the same dialysis unit were analyzed. Anti-HCV antibodies were detected using a 2nd-generation ELISA assay and in all positive cases a RIBA 3rd-generation test was performed. HCV-RNA was tested by a reverse transcription-nested polymerase chain reaction (RT-PCR) assay with primers located in the 5' region. PCR products were analyzed by a nonradioactive hybridation assay. The presence of anti-HCV antibodies was detected in 30 (40%) patients by means of ELISA II test; 28 of them were RIBA III positive and two indeterminate. Twenty-four of the 30 HCV Ab ELISA II positive patients (80%) were HCV-RNA positive (23 RIBA III positive and 1 indeterminate). Six anti-HCV Ab ELISA II positive patients tested negative for HCV-RNA (20%); 5 of these patients were also positive for anti-HCV antibodies with a RIBA III test and 1 was indeterminate. None of the anti-HCV negative patients was HCR-RNA positive. In two cases we documented the disappearance of viremia after an acute HCV infection, with the persistence of antibody reactivity. In conclusion, anti-HCV antibody positive hemodialysis patients should be considered as potentially infectious.

Adult

[Dialysis treatments outside the hospital].

In the early sixties a dramatic lack of hospital dialysis facilities prompted the development of home dialysis programs. The same reasons favoured in Turin, several years later, the start of a home-dialysis program and of the first European self dialysis program in an out-of-hospital setting. In the following years continuous ambulatory peritoneal dialysis was begun. In the last few years we are experiencing a new shortening of in-hospital dialysis facilities; moreover, special attention is devoted to the costs of dialysis treatment, often overlooked in the past. It is likely that self-care and home dialysis will again aid us to solve these problems, as in the past. In this paper we report on the clinical, rehabilitative and socioeconomic results of out-of-hospital dialysis treatments, and on the possible future development of home-hemodialysis and CAPD in Piedmont.

Adult

[Informatics support and teledialysis].

Computer-assisted medical activity is increasing in several fields, with wide perspectives in nephrology and dialysis accounting for the peculiar characteristics of this population such as number, complexity, follow-up length and economic costs. Since 1980 we have been studying a computerized organization of our Region's departments in order to achieve 3 main results: 1) a registry of all patients undergoing dialysis in the area, with a one- a-year complete clinical update; 2) a computerized medical chart, which could gather all the clinical, technical and managerial aspects of the treatment; 3) a teledialysis program, to follow every session in local and remote stations. The first aim has been reached with useful information for the dialytic policy in the area. The second objective is ongoing with straight evidence of easy, speedy procedures, and accurate data collection. The third goal is on a preliminary phase looking at the safety, reliability and precision of the treatments. Informatic procedures seem to be quite advisable in improving as clinical surveillance of the patients, as technical and managerial aspects of dialysis units.

Hemodialysis Units, Hospital

Sodium-lithium countertransport activity in red blood cells of patients with IgA nephropathy.

In this paper we report some results of our studies on patients with immunoglobulin (Ig)A nephropathy regarding (1) the familiar aggregation of erythrocyte sodium-lithium (Na,Li) countertransport; (2) the association of Na,Li countertransport with the presence of arterial hypertension and lipid abnormalities; (3) the correlation between Na,Li countertransport activity and renal functional reserve; and (4) the preliminary results of a longitudinal study. In 13 families of patients with IgA nephropathy, selected because both parents were available, we found a significant correlation between midparent and offspring Na,Li countertransport activity (Spearman's rank correlation = 0.65; P = 0.023), but no husband-wife relationship. In 49 patients, the activity of Na,Li countertransport was significantly higher in erythrocytes from 20 hypertensive patients than from either 29 normotensive patients or from 36 healthy age- and sex-matched normal subjects. Hyperlipidemic patients had an erythrocyte Na,Li countertransport activity significantly higher than normolipidemic patients and controls. In 17 patients a significant inverse correlation was found between the peak variation of creatinine clearance over baseline value after an oral protein load and the erythrocyte Na,Li countertransport activity (Spearman r = 0.54; P = 0.03). In a longitudinal study of 36 patients followed from 12 to 36 months, those showing a progression toward renal failure had an erythrocyte Na,Li countertransport activity higher than median value. The results of our studies show that in patients with IgA nephropathy a high erythrocyte Na,Li countertransport rate, genetically determined, is associated with the presence of arterial hypertension and lipid abnormalities, and perhaps with a less favorable disease outcome.

Adolescent

[Abnormal erythrocyte sodium transport in patients with adult polycystic kidney and hypertension].

The aim of this work was to evaluate the intracellular Na concentration, the passive Na permeability and the activity of Na, K pump, Na, K cotransport, Na, Li countertransport in the red cells of patients with autosomal dominant polycystic kidney disease (ADPKD) in relationship with their blood pressure status. Sixteen patients with ADPKD and normal renal function (6 males, 10 females, median age 31.5 years, range 20-42 years) and twenty healthy controls (10 males, 10 females, median age 30 years, range 23-47 years) were studied. Eight ADPKD were hypertensive. The rate constant of ouabain-sensitive Na efflux was lower in hypertensive than in normotensive ADPKD patients. The activity of Na,Li countertransport was significantly higher in hypertensive ADPKD patients than in both normotensive patients and control subjects. A significant inverse correlation was found between Na,Li countertransport activity and the rate constant of ouabain-sensitive Na efflux in fresh red cells (rho = 0.62; p = 0.016). Hypertension in patients with ADPKD and normal renal function is associated with abnormalities of red cell sodium transport: an increase of Na,Li countertransport, possibly primitive, and a reduction of Na,K pump in fresh cells, possibly secondary to a circulating inhibitor.

Adult

Allogeneic bone marrow transplantation combined with multiple anti-HIV-1 treatment in a case of AIDS.

A 25-year-old woman with AIDS was submitted to HLA-identical allogeneic BMT after cytoablation with busulphan and cyclophosphamide and combined anti-HIV-1 therapy with zidovudine, IFN-alpha 2 and anti-HIV-1-specific T cell clones. Marrow engraftment occurred after 18 days and tests for HIV-1 were negative after 30 days but the hematologic reconstitution of the patient was poor. A second BM infusion from the same donor was ineffective and treatment with GM-CSF only induced a transient increase of the blood cell count, suggesting iatrogenic damage to the BM microenvironment. The development of ARDS led to the death of the patient 10 months after transplantation. Post-mortem investigation did not reveal any active infections and PCR on autopsy tissues was negative for HIV-1.

Acquired Immunodeficiency Syndrome

Aggregation of erythrocyte sodium/lithium countertransport activity in families of patients with immunoglobulin A nephropathy.

1. We evaluated the inheritance of erythrocyte Na+/Li+ countertransport activity in IgA nephropathy by assessing this parameter in 19 patients with biopsy-proven IgA nephropathy and in their 53 relatives (32 parents and 21 siblings). The possible use of erythrocyte Na+/Li+ countertransport activity as a marker of poor prognosis was also evaluated. 2. A significant correlation was found between 'familial' and proband Na+/Li+ countertransport activity, but not between that of spouses. 3. Mean blood pressure, although within the normal range, and Na+/Li+ countertransport activity were significantly higher in patients with proteinuria than in those without proteinuria. 4. Parents of proteinuric patients had a higher Na+/Li+ countertransport activity than parents of non-proteinuric patients. 5. In IgA nephropathy the inheritance of erythrocyte Na+/Li+ countertransport activity was preserved. Therefore genetic factors could play a role in the non-immunological progression of IgA nephropathy.

Adolescent