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G Arrigo

Publications and source records attributed to G Arrigo.

At least 37 records · Page 2Linked to original sources

Characterization of proteinuria in primary glomerulonephritides: urinary polymers of albumin.

In 142 patients with primary glomerulonephritis (GN), there were polymers of albumin (PAs) in the urine samples of 87% of 15 minimal-change disease (MCD) patients, 52% of 27 focal segmental glomerulosclerosis (FSGS) patients, 51% of 47 membranous glomerulonephritis (MGN) patients, 55% of 20 membranoproliferative glomerulonephritis (MPGN) patients, and 9% of 33 immunoglobulin A nephropathy (IgAN) patients (P = 0.000). In IgAN, only three patients with nephrotic syndrome were PA positive. The PAs were significantly correlated with nephrotic syndrome (NS) (P = 0.000) and with the degree of proteinuria, ranging from 8% in patients with proteinuria less than 0.5 g/d to 58% in patients with proteinuria > or = 15.0 g/d (P = 0.001), but 40% of the nephrotic syndrome patients were PA-negative despite values of proteinuria comparable to those of PA-positive patients, suggesting that the presence of PAs is not simply related to protein loss, but probably to some other unidentified factor or lesion. For 72 patients (43 with NS) (22 FSGS, 36 MGN, and 14 MPGN patients) with normal renal function at entry (serum creatinine, 1.02 +/- 0.23 mg/dL) and a mean follow-up duration of 52 +/- 27 months, for whom PAs were determined and urinary protein characterized by sodium-dodecyl-sulphate polyacrylamide gel electrophoresis (SDS-PAGE) at the beginning of the follow-up period, the functional outcome was correlated with the patterns of proteinuria. Chronic renal failure (CRF) developed in 24% of all 72 patients, in 36% of the PA-positive patients, in 9% of the PA-negative patients (P = 0.007), in 44% of the SDS-PAGE 10-kd mixed glomerulotubular pattern patients, and in 17% of the SDS-PAGE 23-kd mixed-pattern patients (P = 0.001). The association of PAs with the 10-kd pattern enhanced the predictive value for CRF outcome: CRF developed in 62% of the PA-positive patients with the 10-kd pattern compared with 11% of the PA-negative patients with the 23-kd pattern (P = 0.0001). CRF developed in 32% of 43 patients with the nephrotic syndrome, in 48% of the PA-positive patients, and in 11% of the PA-negative patients (P = 0.037); in 50% of the 10-kd patients and in 24% of the 23-kd patients (P = 0.007); and in 70% of the PA-positive patients with the 10-kd pattern and 14% of the PA-negative patients with the 23-kd pattern (P = 0.001). In a retrospective study of 21 treated patients (11 FSGS, nine MGN, and one MPGN patient), a response to therapy with complete or partial remission was observed in 57% of all 21 patients; in 58% of patients with the nephrotic syndrome; in 88% of the PA-negative patients versus 38% of the PA-positive patients (P = 0.027); in 90% of the 23-kd patients versus 27% of the 10-kd patients (P = 0.004); and in 100% of the PA-negative patients with the 23-kd pattern versus 12% of the PA-positive patients with the 10-kd pattern (P = 0.001). In conclusion, urinary PAs are associated with GN characterized by lesions mainly localized in the glomerular capillary wall, with the presence of the nephrotic syndrome, and with the degree of proteinuria. In patients with FSGS, MGN, MPGN, and normal renal function at entry, the presence of polymers has a predictive value for CRF outcome; this value is enhanced by the contemporaneous presence of an SDS-PAGE proteinuric pattern with low molecular weight proteins up to 10-kd, which is known to be associated with diffuse tubulointerstitial lesions. Therefore, the best predictive value for either CRF outcome or for response to therapy was provided by a combination between a marker associated with the degree of proteinuria and the types of GN characterized by lesions mainly localized in the glomerular capillary wall and a marker associated with tubulointerstitial damage (SDS-PAGE mixed glomerulotubular pattern with low molecular weight proteins between 20 and 10 kd).

Adolescent↗

Molecular cloning, expression pattern, and chromosomal localization of the human Na-Cl thiazide-sensitive cotransporter (SLC12A3).

Electrolyte homeostasis is maintained by several ion transport systems. Na-(K)-Cl cotransporters promote the electrically silent movement of chloride across the membrane in absorptive and secretory epithelia. Two kidney-specific Na-(K)-Cl cotransporter isoforms are known, so far, according to their sensitivity to specific inhibitors. We have cloned the human cDNA coding for the renal Na-Cl cotransporter selectively inhibited by the thiazide class of diuretic agents. The predicted protein sequence of 1021 amino acids (112 kDa) shows a structure common to the other members of the Na-(K)-Cl cotransporter family: a central region harboring 12 transmembrane domains and the 2 intracellular hydrophilic amino and carboxyl termini. The expression pattern of the human Na-Cl thiazide-sensitive cotransporter (hTSC, HGMW-approved symbol SLC12A3) confirms the kidney specificity. hTSC has been mapped to human chromosome 16q13 by fluorescence in situ hybridization. The cloning and characterization of hTSC now render it possible to study the involvement of this cotransport system in the pathogenesis of tubulopathies such as Gitelman syndrome.

Adult↗

SDS-PAGE patterns and polymeric albumin in proteinuria of lupus glomerulonephritis.

Proteinuria was characterized by SDS-PAGE and by immunoblotting with anti-human albumin sera for the detection of urinary polymers of albumin (PA) in 40 patients with biopsy proven lupus glomerulonephritis (LN) (6 pts class III WHO, 24 pts class IV, 10 pts class V) with various clinical presentations (nephrotic syndrome with normal or impaired renal function, 14 pts; urinary abnormalities with normal or impaired renal function, 21 pts; clinical remission, 5 pts); in 25 pts, for whom the characterization of proteinuria and the renal biopsy were performed at the same time, the activity and chronicity index scores were calculated. The mixed SDS-PAGE patterns, characterized by the presence of low molecular weight proteins, were the more frequently found; the mixed patterns were significantly associated with interstitial leukocyte infiltration (p = 0.05) and glomerular sclerosis (p = 0.046) and nonsignificantly associated with higher values of serum creatinine; no SDS-PAGE pattern had predictive value on functional outcome at 36 months. Albumin polymers were present in 67% of pts; in active disease they were present in 33% of class III, in 100% of class IV and in 45% of class V WHO (p = 0.026); PA were not present in 5 pts with clinical remission (4 class IV and 1 class V WHO). The presence of PA was significantly associated with high values (> 10) of activity index (p = 0.009) and with extracapillary proliferation (p = 0.041). Serum creatinine was lower in patients without PA (Scr 1.0 +/- 0.4 mg/dl) than in those with PA (Scr 1.5 +/- 1.0 mg/dl), but the difference was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Clinical features of 24 patients on regular hemodialysis treatment (RDT) for 16-23 years in a single unit.

Careful investigation of the clinical conditions of patients on maintenance hemodialysis for about 20 years in a single dialysis unit was of great interest for evaluation of the pathological consequences in long-term survivors of insufficient correction of uremia and of the dialysis treatment "per se". We analyzed the outcomes for a cohort of 116 patients who started RDT before 1976 and the clinical conditions of the 24 patients still on RDT in our unit at the end of 1991 (average duration of treatment = 222 +/- 23 months). Actuarial survival was 72% at 10 years and 43% at 20 years. Rehabilitation of the 24 survivors was rather good: 13 were able to work, 8 were retired or unable to work, but able to care for most personal needs. Actual body weight, anthropometric parameters and biochemical parameters revealed a well-preserved nutritional status. Anemia improved from 23 +/- 7 at the start of RDT to 31 +/- 8 in the 21 patients never treated with erythropoietin. Blood pressure was normal without therapy in 18 patients and elevated in 6. Mild-to-moderate left ventricular hypertrophy was present in all the 6 patients with arterial hypertension and in only 6 of the 18 normotensive patients. The ratio of early diastolic filling to filling during atrial contraction (E/A ratio) was < 1 in 16 patients: it was 1.05 +/- 0.43 in 9 patients with stable intradialysis blood pressure and significantly lower (0.73 +/- 0.15) in 12 patients with recurrent intradialysis hypotension. Supraventricular arrhythmias were detected by Holter monitoring in 41% and ventricular arrhythmias in 35% of patients. Extensive vascular calcifications were present (in 100% of patients in the abdominal aorta), but only 4 patients showed clinical signs of peripheral vascular disease. Subperiosteal resorption was detected radiologically in the hands of 59% of patients. Bone histology, interpretable for only 20 patients, revealed no bone lesions in 1 case (5%), mild mixed osteodystrophy in 3 cases (15%), advanced mixed osteodystrophy in 5 cases (25%), osteodystrophy with predominant hyperparathyroidism in 2 cases (10%), osteodystrophy with predominant osteomalacia in 6 cases (30%), and aplastic bone disease in 3 cases (15%). Moderate aluminum staining was found in only 4 patients and was more marked in earlier biopsies taken before withdrawal of the aluminium-containing phosphate-binding drugs.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

Hepatitis C virus genotype in patients with essential mixed cryoglobulinaemia.

We studied 54 patients with essential mixed cryoglobulinaemia (EMC), (23 males, 31 females) mean age 61 years (range 28-77). Forty-one (76%) had type II cryoglobulinaemia and 13 (24%) type III. Antibodies to HCV were detectable by second-generation ELISA in 49 patients (91%) with confirmed or indeterminate RIBA results. HCV RNA was detected by RT PCR using 5' UTR nested primers; HCV genotypes 1a, 1b, 2 and 3a were identified by genotype-specific core-region nested primers. All patients (49) with antibodies to HCV in their serum were HCV-RNA positive; 27 (55.1%) had HCV subtype 1b and 21 (42.8%) type 2. In one patient the HCV genotype could not be determined. The genotype distribution was not different from that found in patients with chronic hepatitis C without cryoglobulinaemia. However, the presence of HCV subtype 1b correlated significantly with signs of chronic hepatitis and presence of peripheral neuropathy. Severity of disease tended to be worse in patients infected with HCV subtype 1b, but this was mainly due to liver disease. HCV genotypes may influence the clinical expression and, in particular, the severity of liver involvement in patients with EMC. Extent and severity of EMC disease in general may also be affected by the different HCV genotypes. These findings may have therapeutical implications, since the different HCV genotypes respond differently to interferon treatment.

Adult↗

Blood volume modeling and refilling rate estimation in hemodialysis by continuous hemoglobin monitoring.

Eleven bicarbonate hemodialyses (HD) of 6 patients under constant ultrafiltration were continuously monitored with an optical Hb-meter, considered to be a marker of blood volume (BV) changes. A theoretical model was fed experimental data for prediction of blood volume and estimation of vascular parameters, and a time course of rate of refilling was extrapolated. The adequacy of the model was very good for the time course of BV prediction (r2 = 0.85-0.95, n = 11) and for plasma protein concentration (r2 = 0.83-0.86, n = 2). Parameters estimated included (mean-DS): filtration coefficient (Cf) = 0.22 (0.16) dl/min*mmHg, transcapillary hydrostatic pressure (DP) = 17.80 (3.44) mmHg and protein concentration of the refilling fluid (Cref) = 0.45 (0.30) g/dl. In conclusion our study has shown that the model chosen fits the observed BV profile well in all cases, thus the Hb data series can be used for BV dynamic modeling and for estimation of vascular parameters.

Adult↗

Biochemical aspects and clinical perspectives of continuous urea monitoring in plasma ultrafiltrate. Preliminary results of a multicenter study.

We tested a new biosensor for urea monitoring in the ultrafiltrate during PFD in a group of 5 hemodialyzed stable patients. The inspection of the UF-urea profile reflects the dynamical changes of the plasma urea concentration during diffusive dialysis and allows the fitting of the main mathematical models of urea kinetics. The biosensor efficiency was 98.4% on average (SD: 1.5%) at Uf fluxes varying from 45 to 55 ml/min (mean: 51 ml/min; SD: 3.2) and at Uf-urea concentrations varying from 23 to 165 mg/dl. The mean difference between Uf-urea determined by the laboratory method and Uf-urea assayed by the biosensor was -1.07 mg/dl and the 95% confidence interval ranged from -2.01 to 0.13 mg/dl. The mean difference between laboratory plasma urea and Uf-urea from the biosensor was on average -1.9 mg/dl and the estimated limits of agreement with a confidence of 95% were -3.16 and 0.64 mg/dl. Comparison between kinetic models and experimental profiles of plasma urea decrease, evaluations of recirculation and post-dialytic rebound, the role of Kt/V on-line during dialysis were the preliminary clinical applications of this biosensor.

Aged↗

Hearing loss in short- and long-term haemodialysed patients.

BACKGROUND: Hearing loss has been described in patients with chronic renal failure on regular dialysis treatment (RDT) with very different frequency, ranging from 20 to 75%; RDT does not seem to worsen hearing function for at least the first 5 years of treatment; no studies are available on patients on RDT for more than 10 years. METHODS: We performed an audiometric evaluation in 91 patients on RDT for various periods: group I (34 patients), < 5 years; group II (32 patients), 5-10 years; group III (25 patients), > 10 years; patients with histories of chronic otitis, ototoxic drug treatment, and chronic auditory trauma were excluded; the possible correlations with some biochemical parameters (urea, creatinine, PTH) were also looked for. RESULTS: Hearing loss was present in 77% of patients and 69.2% of ears; the percentage of patients with hypoacusia was higher in group III (84%) than in group I (76.3%) and II (71.7%), but the differences were not statistically significant. Hypoacusia was cochlear neurosensory in 61.5%, conductive in 6.5%, and mixed in 9.0% of patients; the percentage of patients with cochlear neurosensory hypoacousia was similar in the three groups (I, 61.7%; II, 59.3%; III, 64%). Hearing loss was of slight to moderate degree and not different in the three groups (I, 22.7 +/- 15 dB; II, 26.9 +/- 6.0 dB; III, 29.1 +/- 8.9 dB). There were no correlations between hearing loss and plasma creatinine and PTH values; patients with plasma urea > 200 mg/dl had higher percentage of hypoacousia (86%) than patients with plasma urea < 200 mg/dl (69%) (P = 0.06). CONCLUSIONS: Hearing loss, mainly cochlear neurosensory in type, is present in a high percentage of patients on RDT even at the beginning of treatment, but no negative effects on hearing can be correlated with the duration of dialysis.

Adult↗

Lack of IgA antineutrophil cytoplasmic antibodies in Henoch-Schönlein purpura and IgA nephropathy.

To verify whether IgA antineutrophil cytoplasmic antibody (ANCA) represents a serologic marker in Henoch-Schönlein purpura (HPS), we examined sera from 41 patients with the disease. Control sera from 28 patients with primary IgA nephropathy (IgA-N), 26 IgG-ANCA-positive vasculitis, and 28 normal controls were also studied. An increased IgA binding to neutrophil cytoplasmic extracts but not to purified ANCA antigens was found in 12.2-14.6% of HSP patients and in 14.3-21.4% of IgA-N patients versus 3.5% of normal controls. IgA binding to neutrophil cytoplasmic extracts correlated with serum IgA levels, IgA-rheumatoid factor, and IgA-fibronectin binding capacity. Moreover, low amounts of IgG and fibronectin were detected as contaminants in neutrophil cytoplasmic extracts and fibronectin could partly inhibit the binding of IgA to "crude" extracts. We conclude that IgA-ANCA are neither diagnostically nor immunologically specific in HSP and IgA-N. Several factors present in the sera of patients with IgA-related nephropathies seem to contribute to the "false-positive" IgA-ANCA demonstrable in these patients.

Adolescent↗

Bronchial responsiveness in patients on regular hemodialysis treatment of very long duration.

Several mechanisms (trapping of neutrophils, increased extravascular lung water, left ventricular hypertrophy, metastatic lung calcification, and iron deposition) may impair pulmonary function and alter bronchial responsiveness in patients on long-term regular dialysis treatment (RDT), but no studies have been published concerning patients on RDT for a very long time. To assess bronchial reactivity, a methacholine inhalation test was performed 2 to 24 hours after a dialysis session in 19 patients with RDT duration of almost 20 years (221 +/- 26 months) (group 1) and in 14 patients on RDT for a shorter time (24 +/- 22 months) (group 2); all patients had normal standard pulmonary function test results (group 1: forced vital capacity, 95% +/- 13% and forced expiratory volume in one second [FEV1]: 97% +/- 17%; group 2: forced vital capacity, 108% +/- 11% and FEV1, 108% +/- 9% of expected values). The methacholine provocation dose causing a 20% decrease in FEV1 was significantly lower than normal in seven (37%) group 1 patients and only in one (7%) group 2 patient; this difference was statistically significant (P = 0.049). There were no correlations between bronchial hyperresponsiveness and interdialysis weight gain, left ventricular hypertrophy, diastolic dysfunction expressed as the ratio between early diastolic filling and filling during atrial contraction, secondary hyperparathyroidism, and iron overload. Therefore, bronchial hyperresponsiveness is present in a substantial percentage of patients on RDT of very long duration, but the cause is unknown.

Adult↗

Diagnostic significance and antigen specificity of antineutrophil cytoplasmic antibodies in renal diseases. A prospective multicentre study. Italian Group of Renal Immunopathology.

In a prospective multicentre study on the clinical significance of ANCA in renal diseases, sera from 920 patients with rapidly progressive renal failure and/or renal disease in association with extrarenal signs suggestive of a systemic vasculitis were tested for the presence of ANCA by indirect immunofluorescence (IIF) and ELISA. 193 of 920 cases (20.9%) were positive by IIF and 180 (19.5%) by ELISA, using a 'crude' cytoplasmic extract as substrate. The sensitivity and specificity of IIF for 'pauci-immune' cresentic necrotizing GN (CNGN), in association or not with systemic vasculitis, was 87.5 and 95.6% respectively. The IIF pattern and antigen specificity (alpha granules and MPO) correlated well with the clinical features: a cANCA pattern (alpha granules) was associated with ENT involvement (probable Wegener's granulomatosis); a pANCA pattern (MPO) with 'idiopathic' CNGN and small-vessel vasculitis without respiratory tract disease (microscopic polyarteritis); patients with a pulmonary-renal syndrome had either c or pANCA in a similar proportion. Our study confirms a high sensitivity and specificity of ANCA for patients with CNGN. ANCA should be considered an important diagnostic test in patients with renal diseases, especially in the presence of rapidly progressive renal failure.

Antibodies, Antineutrophil Cytoplasmic↗

Blood lead in hemodialysis patients.

Blood lead corrected for hematocrit (PbC) was measured in 115 hemodialysis (HD) patients. Information was collected with a questionnaire about personal and environmental factors thought to influence blood Pb levels. HD patients had significantly higher mean blood Pb than healthy subjects (p < 0.001). A non-negligible percentage of the HD population (13%) had values over 30 micrograms/dl, the threshold for risk in occupational exposure, and 4% over 40 micrograms/dl which reflects Pb intoxication. No association was found between sex, age, duration of HD and PbC. The prevalence of high diastolic blood pressure was associated with PbC over 30 micrograms/dl (p < 0.01). Also, at blood Pb levels generally considered as 'nontoxic' (less than 40 micrograms/dl), we found a low correlation with diastolic blood pressure (r = 0.19, p = 0.049). A correlation was found between PbC and parathyroid hormone (r = 0.22, p = 0.01) and between PbC and mean corpuscular volume (r = -0.21, p = 0.02). The patients with individual risk factors (smoke, alcohol consumption and alkyl Pb from air contamination) had PbC levels higher than patients without (p = 0.001). The patients with environmental risk factors (professional exposure, tap water consumption and older houses) had PbC levels higher than patients without (p = 0.01). Patients with past occupational exposure had the highest mean PbC levels (34.1 micrograms/dl = 1.65 nM/ml).

Blood Pressure↗

Evoked potentials (VEPs and BAEPs) in a large cohort of short- and long-term haemodialysed patients.

To evaluate the presence and the severity of uraemic encephalopathy (UE) in regular dialysis treatment patients in relation to dialytic age, pattern reversal visual evoked potentials (PRVEPs) and brainstem auditory evoked potentials (BAEPs) were respectively performed in 86 and 98 patients on haemodialysis for 1-194 months, divided into three subgroups according to dialytic age (group 1, < 5 years of regular dialysis; group 2, 5-10 years; group 3, > 10 years). VEPs in the whole group of 86 patients and in each subgroup with different dialytic age differed significantly from controls for both eyes, 41.7% of whom had pathological P100; no differences were observed between the three subgroups. BAEPs were pathological in 9.7% of the ears and 18.4% of patients. On the right ear the three subgroups were significantly different from controls in the latencies of peaks III and V; subgroup 2 and 3 differed from controls in the I-V interpeak, while the interpeak I-III was different from controls only in subgroup 3. On the left ear the three subgroups differed significantly from controls in the latencies of peak V; subgroup 2 and 3 were significantly different from controls in the latency of peak I; subgroup 3 was different in the peak III latency; subgroup 1 and 3 were different from controls in the interpeak I-V; no differences were observed in BAEPs between the three subgroups with increasing dialytic age. No significant correlations were found between the neurophysiological parameters and some biochemical parameters (urea, creatinine, PTH).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Low doses of drugs able to alter intestinal mucosal permeability to food antigens (5-aminosalicylic acid and sodium cromoglycate) do not reduce proteinuria in patients with IgA nephropathy: a preliminary noncontrolled trial.

In an uncontrolled trial, patients with IgA nephropathy (IgAN) were treated with drugs that can alter the intestinal mucosal permeability to food antigens. These drugs are known to ameliorate urinary abnormalities and histological lesions of IgAN associated with ulcerative colitis or Crohn's disease [5-aminosalicylic acid (5-ASA)] or to prevent, in mice, the induction of IgAN-like disease by oral immunization [disodium cromoglycate (SCG)]. Nine patients [serum creatinine (s-Cr) less than 2 mg/dl; 24-hour proteinuria higher than 1.5 g, but not nephrotic) were treated with 5-ASA (2.4 g/day for 6 months); 9 similar patients were treated with SCG (400 mg/day for 6 months); the follow-up extended to 6 months after stopping therapy. The 5-ASA group showed a slight but not significant decrease in s-Cr, 24-hour/proteinuria, IgA circulating immune complexes (IgA-CIC) and IgA rheumatoid factor (IgA-RF); serum beta 2-microglobulin and serum IgA were unchanged; 2 of 9 treated patients showed, after 6 months of therapy, a reduction in proteinuria of more than 50% that lasted for the subsequent 18 months. The SCG-treated group showed a slight but not significant increase in 24-hour proteinuria and a significant decrease in serum IgA; unchanged were s-Cr, IgA-CIC, IgA-RF, serum beta 2-microglobulin; no patient treated with SCG showed a reduction in proteinuria of more than 50%. At the dosages and for the periods used, 5-ASA and SCG did not show a significant influence on clinical and laboratory parameters of disease in IgAN; other trials with increased dosages are warranted to definitely ascertain the possible therapeutic role of these drugs in IgAN.

Adult↗

[Chronic headache].

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Acetylglucosaminidase↗