PubMed Health⌕ Search

Biomedical subjects

S Saffioti

Publications and source records attributed to S Saffioti.

At least 37 records · Page 2Linked to original sources
PubMed1993

Erythropoietin treatment and amino acid metabolism in hemodialysis patients.

A previous report suggests that treatment with recombinant human erythropoietin (rH-EPO) significantly improves many abnormalities in circulating amino acids (AA) in hemodialysis patients. We evaluated the effects of a 12-month treatment with rH-EPO (150-250 U/kg/week) on blood AA levels in 10 patients with chronic renal failure under regular dialytic treatment. During treatment, hemoglobin levels increased from 7.0 +/- 0.3 to 10.1 +/- 0.3 g/dl at 3 months remaining steady thereafter. Before the treatment, patients showed reduced levels of essential AA (EAA), mainly valine, leucine and threonine (p < 0.05-0.01); among non-EAA (NEAA), aspartate and serine were reduced, whereas glycine, alanine, proline, citrulline and cyst(e)ine were increased (p < 0.05-0.001). Val/Gly, Ser/Gly and Tyr/Phe ratios were low (p < 0.05-0.01). Total EAA and total NEAA (619 +/- 21 and 1,382 +/- 75 mumol/l, respectively, before the study) were unchanged (639 +/- 22 and 1,410 +/- 89 mumol/l, respectively) at 12 months. Abnormalities in AA levels observed before the treatment persisted throughout the study. Only serine increased at the end of the study (p < 0.05). In conclusion, contrary to what has been reported, treatment with rH-EPO is not associated with an amelioration of AA metabolism in hemodialysis patients.

Adult↗
PubMed1992

Sonographic detection of renal changes in pseudoxanthoma elasticum.

Pseudoxanthoma elasticum (PXE) is a rare hereditary disease whose basic abnormality is degeneration of elastic tissue, with calcification of the tonaca media of the arteries, and typical yellowish papules of the skin. We report the sonographic findings observed in a young patient with PXE at the level of the kidneys: fine hyperechogenic spots suggesting small calcifications were diffuse at the corticomedullary junction; however, normal waveforms were obtained at the level of intraparenchymal renal vessels. The presence of this structural pattern in a young patient with dermatologic abnormalities should lead to the consideration of PXE in the differential diagnosis list.

Adult↗
PubMed1991

Renal ammoniagenesis in humans with chronic potassium depletion.

Renal ammonia production and distribution and ammonia precursor utilization were evaluated in eight patients with chronic potassium depletion (CPD) and aldosterone-producing adenoma and in 20 controls. In CPD, urinary ammonia excretion and ammonia added to renal venous blood were about twofold higher than in controls; thus, total ammonia production was significantly augmented (88.0 +/- 10.3 mumol/min.1.73 m2 vs. 45.0 +/- 2.6 in controls). Total ammonia production was inversely correlated with serum potassium and directly correlated with urine flow. Stepwise multiple regression analysis showed that both factors, mainly serum potassium, significantly influence ammonia production and account for 61.4% of variations in ammonia production. Renal extraction of glutamine was significantly increased (56.6 +/- 5.9 mumol/min.1.73 m2 vs. 34.6 +/- 3.1 in controls), and this could account for ammonia production. The ratio of urinary ammonia excretion to total ammonia production, an index of the intrarenal ammonia distribution, was similar in patients and controls, and was significantly correlated with urine pH and true renal blood flow (RBF). Stepwise multiple regression analysis showed that RBF, urine pH and urine flow also significantly affected ammonia distribution. However, these factors accounted for only 41.7% of variations in intrarenal ammonia partition, urine pH having a minor role. We conclude that in patients with CPD other factors besides urine pH, urine flow and RBF intervene in the ammonia partition between urine and blood.

Acid-Base Equilibrium↗
PubMed1991

[Captopril-induced changes in renal flow: evaluation using Doppler echography].

It is well known that angiotensin antagonists cause increase of renal blood flow. We have examined, using duplex Doppler sonography, the changes of renal blood flow velocity induced by oral administration of 50 mg. of Captopril. We examined 19 kidneys in 17 subjects without hypertension. Both peak systolic and diastolic velocities were measured at renal hilum and at arcuate arteries, and the resistive index (RI) was calculated. In conclusion duplex Doppler sonography shows significant increase of blood flow velocities both at the hilum and at the arcuate arteries, without variation of the RI, thus showing that changes affect the whole Doppler wave, both in systole and diastole.

Blood Flow Velocity↗
PubMed1989

Free and sulfoconjugated catecholamines in normotensive uremic patients: effects of hemodialysis.

In 9 normotensive uremic patients undergoing chronic hemodialysis, the baseline plasma catecholamines varied widely from low-normal to very high; sulfoconjugated plasma catecholamines were constantly high. A dialysis-induced fall of all sulfated catecholamines and epinephrine was observed. Norepinephrine decreased in 5 patients and increased in 4, with a strong inverse correlation between predialysis norepinephrine and delta norepinephrine (p less than 0.0001). No correlation was evident between clinical parameters (mean arterial pressure, heart rate) and catecholamines (both predialysis and postdialysis). Significant (p less than 0.0001 and p less than 0.0002) inverse correlations between epinephrine and norepinephrine and their sulfoconjugation degree were demonstrated only in predialysis. Our data may support the presence of a uremic autonomic neuropathy and adrenoceptor damage.

Adult↗
PubMed1989

Successful treatment of mitomycin C-associated hemolytic uremic syndrome by plasmapheresis.

Therapeutic attempts have generally failed to reverse the rapid progression of renal failure after mitomycin C (MMC)-induced hemolytic uremic syndrome (HUS). A patient who developed HUS after MMC and who showed pathologic changes in the kidney consistent with thrombotic microangiopathy is reported. Treatment with plasmapheresis was followed by a favorable outcome and significant recovery of renal function. Accordingly, this therapeutic modality should be considered for patients with MMC-induced HUS.

Adult↗
PubMed1987

Effect of amino acid ingestion on blood amino acid profile in patients with chronic renal failure.

Arterial whole blood levels of amino acids (AA) were determined in patients with chronic renal failure (CRF) and in healthy volunteers before and for 75 min after the ingestion of an AA mixture simulating the AA content of an animal-protein meal. In CRF patients, total AA increased more than in control subjects as a consequence of an exaggerated rise in nonessential AA (+86%), mainly glutamine, proline, glutamate, serine, glycine, and alanine. Total essential AA in patients increased as much as in control subjects; however, threonine and phenylalanine showed greater increases while leucine had a smaller increase. As a consequence of the observed alterations, a striking unbalance in the postprandial pattern of arterial AA ensued in CRF patients. The flow of AA to all the organs is altered during the absorptive phase, which is crucial for body nitrogen-pool replenishment.

Adult↗