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S Morano

Publications and source records attributed to S Morano.

At least 37 records · Page 2Linked to original sources

Selective decrement of anionic immunoglobulin clearance after induced renal hemodynamic changes in diabetic patients.

The charge permselectivity of proteins was evaluated in diabetic patients after systemic and renal hemodynamic changes induced by an intravenous injection of an angiotensin-converting enzyme inhibitor (captopril) or of clonidine. Anionic immunoglobulin clearance (IgG4) was compared with that of total immunoglobulins, which have the same size but are mostly cationic, and of albumin. Ten type I hypertensive diabetic patients (group 1), 10 type 2 hypertensive diabetic patients (group 2), 5 type 1 normotensive diabetic patients (group 3), 10 subjects with essential hypertension (group 4), and 7 normal volunteers (group 5) received an intravenous injection of captopril (25 mg/100 ml in 5 min). Twelve of the hypertensive diabetic patients underwent a second provocative test with clonidine (150 micrograms/100 ml) (group 6) or placebo (100 ml saline) (group 7) with the same procedure. None of the patients had clinical nephropathy or other disorders. Glomerular filtration rate (GFR) and renal plasma flow (RPF) were measured before and during the tests. A significant decrease in diastolic blood pressure was observed in groups 1, 2, 4, and 6, together with an increase in the GFR and RPF values in groups 1, 2, 3, and 4 only, as well as a decrease in renal vascular resistances in groups 1, 2, 3, 4, and 6. Both clearances and fractional clearances of IgG4 and IgG decreased after captopril in groups 1 and 2.2+ The decrease in IgG4 clearance was correlated to that of renal vascular resistances in group 1 patients. A significant decrease in the anionic-cationic immunoglobulin ratio (IgG4/IgG) was observed in groups 1, 2, and 3.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Charge selectivity of proteinuria in type I diabetes explored by Ig subclass clearance.

To investigate the role of protein charge in early diabetic proteinuria, the clearance of proteins differing in charge and/or size (anionic and cationic Igs, albumin) was evaluated in 98 insulin-dependent (type I) diabetic patients selected as a representative sample of the 418 patients attending our clinics. Of the patients, 12.9% were microalbuminuric and 4.8% were macroalbuminuric. Anionic and total IgG clearances were significantly increased in 30.6 and 12.2% of patients and were correlated with duration of disease. Anionic IgG4 clearances were increased in patients (9.2%) with normal IgG excretion, suggesting that charge-selectivity impairment is responsible for protein loss. Anionic Ig clearances were also higher in some patients (14.3%) with normal albumin clearance, probably as a result of different glomerular filtration and/or tubular reabsorption. The anionic-cationic IgG clearance ratio tended to increase in parallel with albumin clearance, but once above macroalbuminuric levels, it tended to fall again, indicating the concomitant presence of size-selectivity loss. The anionic IgG clearance and the anionic-cationic IgG ratio, in addition to albumin excretion, may be valuable in assessing early kidney protein charge-selectivity impairment and better characterizing normoalbuminuric patients and those in the preclinical stage of diabetic nephropathy.

Adult↗

Abnormalities of cognitive functions in IDDM revealed by P300 event-related potential analysis. Comparison with short-latency evoked potentials and psychometric tests.

The possible influence of diabetes on the higher mnestic and cognitive functions has been investigated. The P300 wave latency, an endogenous electrophysiological event, was explored and compared with the multimodal short-latency evoked potential (EP) recordings (visual [VEP], brainstem auditory [BAEP], and median and tibial nerve somatosensory EPs [mSEP and tSEP, respectively]) and psychometric test measures in 16 insulin-dependent diabetic (IDDM) patients, in 16 age- and (IDDM) sex-matched nondiabetic subjects, and in a large normal reference population. The age of subjects, the duration of IDDM, and the metabolic control of patients were taken into account. P300 values were significantly increased in IDDM versus matched control subjects (P less than 0.001), and 3 patients showed values above the reference value range. Abnormal VEP recordings were present in 1 of 16 patients, BAEP in 3 of 16, mSEP in 7 of 16, and tSEP in 6 of 16. Digit-span backward test results were significantly (P less than 0.02) modified in the diabetic cohort. There was no tendency for anomalies of P300, short-latency EPs, and psychometric test values to be contemporarily present, except in 1 patient. Electrophysiological or psychometric abnormalities were not clearly correlated with the duration of IDDM or the degree of short-term metabolic control. These findings give evidence that 1) higher cognitive functions may be affected in diabetes as documented by P300 analysis and short-term memory tests, 2) endogenous electrophysiological analysis highlights neuropsychological changes not detectable by psychometric tests, 3) an alteration of evoked potentials was present in half of the IDDM subjects studied, and 4) anomalies of the CNS are patchily distributed in diabetes.

Acoustic Stimulation↗

Efficacy of antihypertensive treatment with indapamide in patients with noninsulin-dependent diabetes and persistent microalbuminuria.

In patients with insulin-dependent diabetes, antihypertensive treatment has a beneficial effect on the rate of progression toward uremia of overt diabetic nephropathy (albumin excretion rate [AER] greater than 300 mg/24 hour). The influence of hypertension on the progression of "incipient" nephropathy (AER ranging between 30 and 300 mg/24 hours) is not well defined, particularly in patients with noninsulin-dependent diabetes. In this study, 21 patients with noninsulin-dependent diabetes and hypertension (11 with normoalbuminuria and 10 with microalbuminuria), who were comparable for age, duration of diabetes and hypertension, were treated with indapamide, 2.5 mg once daily, and followed up for 24 months. Blood pressure, glomerular filtration rate (GFR), albumin excretion rate and subclass 4 of urinary immunoglobulin G (IgG4) were indicated. In normoalbuminuric patients, blood pressure was significantly reduced, whereas AER, IgG4 and GFR did not show any variation throughout the study. In microalbuminuric patients, blood pressure, AER and IgG4 were significantly reduced, and GFR remained unchanged. In patients with noninsulin-dependent diabetes, antihypertensive treatment, which is begun during incipient diabetic nephropathy, may have a beneficial effect on the progression of the disease, although a long-term follow-up study is needed to confirm this.

Adult↗

New parameters to monitor the progression of diabetic nephropathy.

The possible differential elimination of the anionic IgG4 and of the other cationic IgG molecules whose pH differs but whose other characteristics are similar, has been hypothesized as a possibly useful parameter in monitoring preclinical diabetic nephropathy. An enzyme-linked immunosorbent assay method has been developed, based on a sandwich technique with subclass-specific antiimmunoglobulin monoclonal antibodies, which detects about 2 ng/mL IgG4. A sensitive radioimmunoassay method has been used to detect IgG. Normoalbuminuric, microalbuminuric, and macroalbuminuric patients, together with normal control subjects, were included in the cross-sectional study. Whereas IgG levels were elevated, as expected, in macroalbuminuric patients, it was interesting to note that IgG4, but not total IgG, levels were elevated in microalbuminuric patients. The IgG4/IgG ratio was increased almost to the same extent in microalbuminuric and macroalbuminuric patients. These findings are strongly in favor of the selective elimination of the acid medium-sized protein, IgG4, in incipient diabetic nephropathy. The measurement of immunoglobulin subclasses in the urine appears to be a promising parameter to characterize and subgroup diabetic patients with preclinical diabetic nephropathy.

Adolescent↗

D-lysine effectively decreases the non-enzymic glycation of proteins in vitro.

Excessive non-enzymic glycation of proteins alters their physicochemical properties, with possible pathological effects. We investigated the in vitro inhibition of protein glycation by D-lysine--an isomer not incorporated into mammalian proteins but possessing the same chemical characteristics as L-lysine. Glucose incorporation was studied as follows: (a) human albumin, IgG, collagen, and isolated glomerular basement membrane were incubated for 20 days with D-glucose (5.0, 10.0, and 20.0 mmol/L) in the presence of D-lysine at 1/10 the sugar concentration; (b) albumin was incubated in similar glucose concentrations but with a constant amount (2.0 mmol/L) of D-lysine; (c) albumin and IgG were incubated for 10 days in buffer containing glucose (10 mmol/L) and increasing concentrations of D-lysine (0.25, 0.5, 1.0, 2.0, and 4.0 mmol/L); (d) inhibition specificity was tested by treating albumin as in c but with glycerol present rather than D-lysine. In addition, we measured ketoamine after incubating albumin (50 g/L) in 10 mmol/L glucose for 10 days in the presence of D-lysine (0.25, 0.5, 1.0, and 2.0 mmol/L). The results show that (a) the amount of glucose bound to the four proteins was significantly (P less than 0.05) decreased in the presence of D-lysine at the higher concentrations of glucose; (b) the lower the glucose concentration, the higher was the inhibitory effect of D-lysine; (c) the inhibition of glucose incorporation into proteins correlated directly with the concentration of D-lysine; (d) no inhibition was observed with glycerol. Ketoamine decreased with increase in D-lysine (P less than 0.01). The effective diminution of non-enzymatic glycation by D-lysine highlights its potential use in vivo.

Basement Membrane↗

Urinary IgG4: an additional parameter in characterizing patients with incipient diabetic nephropathy.

In the natural history of diabetic nephropathy there is a progressive impairment of protein permselectivity. The early increased excretion of anionic proteins may be explained by the initial loss of charge selectivity of the filtration filter. In comparison to other immunoglobulin subclasses, IgG4 has the same molecular weight but an acid isoelectric point: its possible selective urinary elimination could indicate a charge selectivity impairment in the preclinical stage of diabetic nephropathy. To verify this hypothesis, 53 Type 1 diabetic patients, grouped according to their albumin excretion rate (AER) (23 showed an AER less than 35 micrograms/min, Group I; 19 between 35-200 micrograms/min, Group II; 11 an AER greater than 200 micrograms/min, Group III), and 20 normal subjects were tested for urinary IgG4, total IgG, and other nephrological and metabolic parameters. Urinary IgG4 and IgG were detected with solid phase methods (ELISA and RIA respectively) developed in our laboratory. Urinary total IgG values were significantly higher in Group III in comparison with Group I and II and with normal subjects. Urinary IgG4 values were significantly increased in Group III, as well as in Group II, in comparison with Group I and normal controls. IgG4/IgG ratio values were significantly increased in both Groups II and III in comparison with Group I and control subjects. Whereas IgG values were within the normal range in Group II, IgG4 values were clearly elevated, thus demonstrating a selective elimination of this acid, medium-sized protein. Urinary IgG4 could be an additional parameter to characterize more precisely and subgroup microalbuminuric patients.

Adolescent↗

A longitudinal study of multimodal evoked potentials in diabetes mellitus.

Abnormal findings in visual (VEP), brainstem auditory (BAEP) and somatosensory (SEP) evoked potentials at early stages of Type 1 and Type 2 diabetes have recently been reported by our group. Our aim here was to perform a longitudinal study in diabetic patients at an early stage of the disease using a combined evoked potential analysis in order to evaluate the variation of neurological abnormalities over time. Nine Type 1 and 12 Type 2 diabetic patients were examined and a second recording was carried out after a mean interval of 15.7 months +/- 6.2 SD. VEP, BAEP and SEP were measured in all patients. At the first recording electrophysiological abnormalities, present in both Type 1 and Type 2 diabetes were more evident when a multimodal evaluation was used (44.4% and 66.7% respectively). The follow-up study showed that overall neurological abnormalities persisted in all those patients who had previously presented pathological values. Whereas the number of patients with pathological values remained unmodified, a tendency to progression, namely the number of nervous levels with electrophysiological abnormalities, was observed. Thus, our study confirms the appearance of anatomofunctional disorders in the central nervous system in short-term diabetes, shows the persistence of neurological impairment in such patients and reveals a progressive segmental involvement at different nervous levels.

Acoustic Stimulation↗

Early detection of neurological involvement in IDDM and NIDDM. Multimodal evoked potentials versus metabolic control.

Clarification of the extent and mechanisms of damage to the central nervous system in diabetes is a frontier of current neurological research. Our aim was to obtain ample electrophysiological documentation of possible neurological abnormalities in both insulin-dependent (IDDM) and non-insulin-dependent (NIDDM) diabetic patients with a short duration of disease and without overt complications, taking into account metabolic control. Group 1 comprised 11 IDDM patients, and group 2 included 14 NIDDM patients treated with diet alone; the duration of disease was less than 4 yr, and no concomitant clinical complications were present. Age- and sex-matched normal subjects formed groups 3 and 4. Pattern visual evoked potentials (VEP), brain stem auditory evoked potentials (BAEP), and somatosensory evoked potentials (SEP; after the stimulation of both median and tibial nerves) were recorded in all subjects, and metabolic control was evaluated in terms of glycemia and glycosylated hemoglobin. In group 1, significant abnormalities were found in the latency values of VEP, median SEP, and tibial SEP compared with control subjects. Similar latency abnormalities were shown in group 2 for VEP, median SEP, and tibial SEP values and for wave I latency of BAEP. Glycosylated hemoglobin values were correlated with BAEP and SEP abnormalities in many patients in both groups. Furthermore, in group 2, glycemic values correlated with SEP abnormalities. We therefore conclude that neurophysiological abnormalities are present at different levels in IDDM and NIDDM patients only a few years after clinical diagnosis and before the appearance of overt complications, and these abnormalities seem to be correlated with metabolic control status.

Adult↗

Sensitive immunoenzymatic assay for urinary immunoglobulin subclasses of different pH: its significance in diabetic patients.

In search of a marker for monitoring the progression of diabetic nephropathy from the stage of charge- to that of size-selectivity loss, attention has been focused on the evaluation of immunoglobulin G (IgG) subclasses in the urine. We have developed a new sensitive enzyme immunoassay for the quantitation of urinary IgG1 and IgG4. Mouse monoclonal antibodies specific for each subclass were bound to microtitre wells precoated with rabbit anti-mouse immunoglobulin antibody. IgG1 and IgG4 of standard preparations (or of samples to be tested) were revealed using peroxidase-conjugated rabbit anti-human IgG. The procedure was carried out at 4 degrees C. This method can detect about 2 ng/ml of IgG4 and 20 ng/ml of IgG1. The monoclonal antibodies used were shown to be highly subclass-specific. IgG1 and IgG4 have a similar molecular weight but a different pH (about 9 and 4.6 respectively); a change in their ratio in the urine of diabetic patients may indicate a progressive deterioration of kidney function at the stage of incipient diabetic nephropathy.

Diabetic Neuropathies↗

A sensitive routine assay for urinary albumin based on the competitive binding to anti-albumin antibodies in solid phase.

The detection of microalbuminuria has a high prognostic value in diabetic patients with no symptoms of clinical nephropathy. Attention has been focused on the development of a simple, reproducible, specific, and, above all, sensitive method to detect albuminuria in the urine. The method is based on the competitive binding between albumin in the urine to be tested and a fixed amount of radiolabelled albumin to anti-albumin immunoglobulins in solid phase. The immunoglobulin C fraction of a rabbit anti-human albumin antiserum was left to coat highly adsorbent polystyrene microtitre tubes. While the aspecific tube binding was overcome by saturation with a solution of gelatine, increasing dilutions of standard albumin or the diluted urine samples to be tested were left to incubate with an equal volume of radiolabelled albumin at room temperature for 1 hour. The cold/hot albumin mixture was added to anti-albumin immunoglobulin-coated tubes, which had been repeatedly washed, and left to incubate. After washing, radioactivity was assessed. This assay has proved to be fast, simple and highly sensitive since it detects up to 25 ng of albumin per ml and is of value in large-scale screening for microalbuminuria in diabetic patients.

Albumins↗

Urinary immunoglobulin G: a routine and highly sensitive technique based on competitive binding.

The evaluation of both small amounts of urinary immunoglobulins and the albumin/immunoglobulin ratio are important indices during the early stages of diabetic nephropathy. For this reason there is at present a need for highly-sensitive and specific routine tests for urinary immunoglobulins. A technique has been designed based on the competition between radiolabelled immunoglobulin G and immunoglobulins in the urine to be tested in binding to an anti-immunoglobulin antibody in solid phase. The immunoglobulin fraction of a rabbit anti-human immunoglobulin antiserum in a basic Ca-carbonate buffer is left to coat highly adsorbent polystyrene microtitre tubes. After the antibody-coated tubes have been saturated with gelatine, a 1/5 dilution of the urine to be tested and an equal volume of purified and radiolabelled human immunoglobulin G are left to incubate and are then added to the antibody-coated tubes. After incubation and repeated washings, radioactivity is counted. This technique has the characteristics of a routine assay for the accurate detection of immunoglobulin G in the urine. It requires only a few microliters of urine, takes only 3 hr to complete (after having coated the tubes) and detects about 120 ng of immunoglobulin G/ml, well below what is needed to assess physiological or pathological values.

Binding, Competitive↗

A fluid-phase routine method for the detection of insulin-anti-insulin complexes.

A fast routine method has been devised to measure circulating insulin-anti-insulin complexes. The principle lies in the calculation of the difference between the insulin binding capacity of the free antibody and that of the total amount of insulin antibody. The pH of 1 aliquot of serum was lowered to 3 by adding glycine-HCl buffer. Free insulin was removed by charcoal precipitation and the pH was again neutralized by the simple addition of NaOH; the final dilution of serum was 1/5. Radiolabelled insulin was added to this and to a second aliquot of serum, also diluted 1/5. Free and bound insulin were separated using either dextran charcoal or PEG 6000 at a final dilution of 14.3%. The first technique of separation was preferred. This method has been used in normal controls and in insulin-treated diabetic patients and the results have been compared to those obtained using other methods to detect insulin-anti-insulin complexes and insulin antibodies. Insulin-anti-insulin complexes tended to be more frequently observed in patients with high insulin antibody values. The technique described is much less laborious than other methods for detecting insulin complexes since it requires only a few hours to complete. It is reproducible and sensitive enough for clinical research. This method is of value when both free and bound insulin antibodies have to be evaluated.

Animals↗

[Effect of veralipride on LH, FSH, and PRL levels and on the climacteric syndrome].

21 women with menopausal disorders were given veralipride, which is a benzamide derivative having a central anti-dopaminergic action. The LH, FSH and PRL plasma levels were controlled before and after treatment. Treatment, using veralipride at a daily dose of 100 mg for 20 days, improved the climacteric syndrome, and, in particular, the sudden hot flushes. The FSH plasma levels remained unchanged, the LH levels were reduced, although they remained high, and the PRL levels increased during the course of the treatment.

Adult↗

Effects of lisuride and bromocriptine on inhibition of lactation and on serum prolactin levels: comparative double-blind study.

The effects of lisuride (Schering) and bromocriptine (Parlodel, Sandoz), two dopaminergic drugs, on the inhibition of puerperal lactation were compared in a double-blind study. At the dosages selected, lisuride was as effective as bromocriptine for the inhibition of lactation but bromocriptine was more effective in lowering serum prolactin levels.

Bromocriptine↗

High glucose modifies heparansulphate synthesis by mouse glomerular epithelial cells.

BACKGROUND: Alterations in proteoglycan metabolism are involved in the pathogenesis of diabetic nephropathy. The aim of this study is to evaluate the effects of high glucose on proteoglycan production and to find a reliable in vitro model for the study of diabetic nephropathy. METHODS: A clone of mouse glomerular epithelial cells was cultured in media containing elevated (30 mmol) and physiological (5 mmol) glucose, or iso-osmolar (30 mmol) mannitol concentrations. We evaluated the synthesis of 35SO4-labeled molecules and the amount of proteoglycans by Sepharose CL6B and DEAE-Sephacel chromatographies. RESULTS: A clear decrease (56%) in total cell-layer proteoglycan synthesis was induced by 30 mmol glucose, in comparison with normal glucose. A reduction of 25% in medium associated proteoglycan synthesis was observed in high glucose cultured cells. After Sepharose CL6B, in cells cultured in high glucose, cell layer heparansulphate proteoglycan-I (Kav 6B 0. 04) synthesis was reduced by about 81%, heparansulphate proteoglycan-II (Kav 6B 0.21) by about 87% and heparansulphate glycosaminoglycan (Kav 0.4-0.8) by about 91%, respectively. In mannitol-incubated cells the reductions observed were less evident and not significantly different from those in normal glucose. CONCLUSIONS: These results indicate that (1) glomerular epithelial cells play a central role in proteoglycan synthesis, (2) high glucose modifies the amount and influences the different species production of these macromolecules, while osmotic forces seem to be only partially involved in these effects, and (3) this cellular clone of glomerular epithelial cells can represent a reliable in vitro model for the study of the mechanisms involved in diabetic nephropathy.

Animals↗