Renal vascular sclerosis is associated with inherited thrombophilias.

Vascular sclerosis is often seen in renal biopsies. It is usually associated with diabetes mellitus, hypertension, smoking, etc. However, whether inherited thrombophilic states such as factor V gene mutation, prothrombin gene mutation, and methylenetetrahydrofolate reductase (MTHFR) gene mutation are associated with the vascular sclerosis is not known. Renal biopsies that showed vascular disease were grouped into five groups: (1) diabetic patients, (2) hypertensive patients, (3) diabetic and hypertensive patients, (4) smokers, and (5) vascular sclerosis of unknown etiology (idiopathic renal disease). Renal biopsies with no vascular sclerosis were used as controls. Frozen tissue was analyzed for factor V Leiden mutation, prothrombin G20210A mutation, and MTHFR C677T. Factor V Leiden mutation and prothrombin G20210A mutation was not seen in patients with diabetes, hypertension, or smoking, whereas MTHFR C677T polymorphism in these groups was not significant, compared to the controls. In the idiopathic renal disease group, three of the 17 patients (17.6%) had prothrombin G20210A mutation, two of the 17 patients (11.8%) had the factor V Leiden mutation, and five of the 17 (29.4%) were homozygous for the MTHFR C677T polymorphism. When the data were evaluated as a whole, 10 mutations were found in 17 patients (P<0.0005 compared to controls) or eight of the 17 patients (47%) were observed to have at least one of the three forms of inherited thrombophilia (P<0.001 compared to controls). These findings indicate that renal vascular lesions, in the absence of diabetes, hypertension, or smoking appears to be associated with inherited thrombophilias.

Optimized aminolysis conditions for cleavage of N-protected hydrophobic peptides from solid-phase resins.

Solid-phase synthesis and aminolysis cleavage conditions were optimized to obtain N- and C-terminally protected hydrophobic peptides with both high quality and yield. Uncharged 'WALP' peptides, consisting of a central (Leu-Ala)n repeating unit (where n = 5, 10.5 or 11.5) flanked on both sides by Trp 'anchors', and gramicidin A (gA) were synthesized using 9-fluorenylmethoxycarbonyl chemistry from either Wang or Merrifield resins. For WALP peptides, the N-terminal amino acid was capped by coupling N-acetyl- or N-formyl-Ala or -Gly to the peptide/resin or by formylation of the completed peptide/resin with para-nitrophenylformate (p-NPF). N-Terminal acetyl- or formyl-Ala racemized when coupled as an HOBt-ester to the resin-bound peptide, but not when the peptide was formylated with p-NPF. Racemization was avoided at the last step by completing the peptide with acetyl- or formyl-Gly. For both WALP peptides and gA, cleavage conditions using ethanolamine or ethylenediamine were optimized as functions of solvent, time, temperature and resin type. For WALP peptides, maximum yields of highly pure peptide were obtained by cleavage with 20% ethanolamine or ethylenediamine in 80% dichloromethane for 48 h at 24 degrees C. N-Acetyl-protected WALP peptides consistently gave higher yields than those protected with N-formyl. For gA, cleavage with 20% ethanolamine or ethylenediamine in 80% dimethylformamide for 48 h at 24 degrees C gave excellent results. For both WALP peptides and gA, decreasing the cleavage time to 4 h and increasing the temperature to 40-55 degrees C resulted in significantly lower yields. The inclusion of hexafluoroisopropanol in the cleavage solvent mixture did not improve yields for either gA or WALP peptides.