Biomedical subjects

A M Valeri

Publications and source records attributed to A M Valeri.

4 recordsLinked to original sources

PubMed2006

Cellular focal segmental glomerulosclerosis: Clinical and pathologic features.

Five pathologic variants of idiopathic focal segmental glomerulosclerosis (FSGS) are recognized: collapsing (COLL), cellular (CELL), glomerular tip lesion (GTL), perihilar, and not otherwise specified (NOS). The prognostic significance of CELL FSGS has not been determined. We compared the presenting clinical and pathologic characteristics in 225 patients with CELL (N=22), COLL (N=56), GTL (N=60), and NOS (N=87) variants of idiopathic FSGS. CELL, COLL, and tip lesion all showed greater frequency and severity of nephrotic syndrome, and shorter time to biopsy compared to NOS. Predictors of end-stage renal disease (ESRD) for all FSGS patients included initial serum creatinine, % global sclerosis, % COLL lesions, chronic tubulo-interstitial injury score, and lack of remission response. COLL FSGS had the highest rate of renal insufficiency at presentation, most extensive glomerular involvement and chronic tubulo-interstitial disease, fewest remissions (13.2%), and highest rate of ESRD (65.3%). GTL patients were older and showed the highest remission rate (75.8%) and lowest rate of ESRD (5.7%). CELL variant showed intermediate rates of remission (44.5%) and ESRD (27.8%) compared to COLL and tip lesion. CELL variant may include cases of unsampled tip or COLL lesion, underscoring the importance of adequate sampling. Our data support the view that CELL and COLL FSGS are not equivalent and validates an approach to pathologic classification that distinguishes between COLL, CELL, and tip lesion variants of FSGS.

Adolescent↗

PubMed2003

Secondary focal segmental glomerulosclerosis in non-obese patients with increased muscle mass.

BACKGROUND: Secondary focal segmental glomerulosclerosis (FSGS) is a pattern of glomerular injury mediated by hyperfiltration and other adaptive structural-functional responses. We describe 3 non-obese patients with elevated body mass index (BMI) owing to increased muscle mass who had renal biopsy findings favoring a form of secondary FSGS. METHODS: Clinical and pathologic data were obtained on 3 patients with 1) renal biopsy findings of focal segmental and/or global glomerulosclerosis with glomerulomegaly; 2) BMI > or = 30; 3) body fat percentage < 20%; 4) "highly muscular" appearance, and 5) proteinuria > or = 1 g/d without nephrotic syndrome. 24-hour urine creatinine excretion was used to estimate lean body mass and percentage body fat. RESULTS: The 3 patients were males (age 38 - 48 years) employed in jobs requiring strenuous physical activity. BMIs ranged from 30.4 - 32.1 kg/m2 with body fat percentages of 12.9 - 16.8%. Creatinine clearances at time of biopsy ranged from 113 - 208 ml/min. Renal biopsies showed focal segmental and/or global glomerulosclerosis affecting a minority of glomeruli with glomerular hypertrophy and minimal (mean 15%) foot process effacement. Treatments included angiotensin-converting enzyme inhibitor, angiotensin II receptor blocker, or weight loss. Over a mean follow-up time of 24.3 months, serum creatinine remained stable and proteinuria decreased in all patients. CONCLUSIONS: Non-obese patients with increased BMI due to elevated muscle mass are at risk of developing a secondary form of FSGS that resembles obesity-related glomerulopathy.

Adult↗

PubMed2001

Obesity-related glomerulopathy: an emerging epidemic.

BACKGROUND: We report the first large renal biopsy-based clinicopathologic study on obesity-related glomerulopathy. METHODS: Obesity was defined as body mass index (BMI)> 30 kg/m2. Obesity-related glomerulopathy (ORG) was defined morphologically as focal segmental glomerulosclerosis and glomerulomegaly (O-FSGS; N = 57) or glomerulomegaly alone (O-GM; N = 14). RESULTS: Review of 6818 native renal biopsies received from 1986 to 2000 revealed a progressive increase in biopsy incidence of ORG from 0.2% in 1986-1990 to 2.0% in 1996-2000 (P = 0.0001). Mean BMI in ORG was 41.7 (range 30.9 to 62.7). Indications for renal biopsy included proteinuria (N = 40) or proteinuria and renal insufficiency (N = 31). Seventy-one patients with ORG were compared to 50 patients with idiopathic FSGS (I-FSGS). Patients with ORG were older (mean 42.9 vs. 32.6 years, P < 0.001) and more often Caucasian (75% vs. 52%; P = 0.003). ORG patients had a lower incidence of nephrotic range proteinuria (48% vs. 66%; P = 0.007) and nephrotic syndrome (5.6% vs. 54%; P < 0.001), with higher serum albumin (3.9 vs. 2.9 g/dL; P < 0.001), lower serum cholesterol (229 vs. 335 mg/dL; P < 0.001), and less edema (35% vs. 68%; P = 0.003). On renal biopsy, patients with ORG had fewer lesions of segmental sclerosis (10 vs. 39%; P < 0.001), more glomerulomegaly (100% vs. 10%; P < 0.001), and less extensive foot process effacement (40 vs. 75%; P < 0.001). Glomerular diameter in ORG (mean 226 mu) was significantly larger than age- and sex-matched normal controls (mean 168 mu; P < 0.001). Follow-up was available in 56 ORG patients (mean 27 months) and 50 idiopathic FSGS controls (mean 38 months). A total of 75% of ORG patients received angiotensin-converting enzyme (ACE) inhibition or A2 blockade while 78% of the I-FSGS patients received immunosuppressive therapy. ORG patients had less frequent doubling of serum creatinine (14.3% vs. 50%; P < 0.001) and progression to ESRD (3.6% vs. 42%; P < 0.001). On multivariate analysis, presenting serum creatinine and severity of proteinuria were the only predictors of poor outcome in ORG. CONCLUSION: ORG is distinct from idiopathic FSGS, with a lower incidence of nephrotic syndrome, more indolent course, consistent presence of glomerulomegaly, and milder foot process fusion. The ten-fold increase in incidence over 15 years suggests a newly emerging epidemic. Heightened physician awareness of this entity is needed to ensure accurate diagnosis and appropriate therapy.

Adult↗

PubMed1980

Reaction of antithrombin with proteases. Evidence for a specific reaction with papain.

Experiments were performed to determine if the sulfhydryl protease, papain (EC 3.4.22.2), reacts with the plasma protease inhibitor antithrombin (antithrombin III, heparin cofactor) on a specific manner analogous to the reaction of thrombin (EC 3.4.21.5) and other serine proteases with this inhibitor. The esterolytic activity of papain is blocked by the addition of antithrombin, but not by antithrombin-thrombin complex or by protein substrates such as bovine serum albumin. Likewise, in the presence of papain, antithrombin was unable to displace the active site dye proflavine from thrombin, or to inhibit thrombin-catalysed hydrolysis of an anilide substrate. The reaction of antithrombin and papain was not accelerated by low concentrations of heparin. Approximately stoichiometric amounts of heparin completely inhibited the reaction of papain with antithrombin. The mutual inhibition indicates that plasma antithrombin does react with papain but the reaction differs from the interaction with coagulation factors, particularly in the heparin effect.

Antithrombin III↗