In Vitro Comparison Study of CD63 and CD62P Expression After Contacting Leukocyte Filters

CD63 and CD62P have been recognized as platelet activation markers. This study investigated the secretion of these antigens to compare the platelet activation between a newly developed stainless steel leukocyte filter (SSLF) and 7 polyester or polyurethane commercially available leukocyte filters. Flow cytometry demonstrated that the SSLF initiated significantly smaller effects in terms of mean fluorescence intensity of CD63 (p < 0.03) and of the amount of CD62P expressing platelets (p < 0.002) compared to the polyurethane filters. However, there was no statistical difference between the SSLF and polyester filters. The result of this study suggests that the SSLF caused less platelet activation than the polyurethane filters and has biocompatible characteristics comparable to the currently available polyester filters. Stainless steel was selected because of its physicochemical conductivity. With these results, further evaluation of the SSLF will be continued in an attempt to develop an active immunomodulator using this unique characteristic.     

Influence of grip types and intensities on force-decreasing curves and physiological responses during sustained muscle contractions

This study examined relationships between force outputs during sustained isometric grips (SIG) and intermittent repeated grips (IRG) with three relative target forces (50%, 75%, and 100% MVC), and subjective muscle-fatigue sensation (SMS) and blood lactate during and after gripping tests. Ten young men performed sustained grip tests with 2 grip types and 3 target forces for 6 min. Lactate and maximal grip strength were measured before, just after and 4 min and 7 min after each grip test. SMS of the forearm was measured every 30 s during and after each grip test. The relationships of average grip force in every 30 s between SIG and IRG were not good. The lactate values after IRG tests with 75% and 100% MVC tended to be higher than in the other conditions. The tendency for decline differs with grip type, intensity (target forces) and the force outputs among the conditions. The muscle fatigue level in the SIG and IRG tests may differ largely even when using the same target force. Although the SIG imposes a larger burden on subjects than the IRG, lactate after gripping work is lower.     

A case of second-degree atrioventricular block caused by high dose cisplatin treatment

A 56-year-old man was admitted to our hospital because of stage IV squamous cell carcinoma of the lung. He was treated with two courses of high dose cisplatin (40 mg/m2/day, day 1-5). On day 4 of each course, a second-degree atrioventricular block was observed, which disappeared after cisplatin treatment. This case suggests that, although the cardiotoxicity caused by cisplatin is believed to be rare, one should take special care in high dose usage.     

Angiotensin-converting-enzyme inhibitors slow renal decline in IgA nephropathy, independent of tubulointerstitial fibrosis at presentation

BACKGROUND: Tubulointerstitial fibrosis (TIF) is a marker of progression of diabetic and non-diabetic nephropathy, correlating with creatinine clearance (CCr), and functional outcome. Angiotensin-converting-enzyme inhibitors (ACEIs) slow the rate of decline of renal function in proteinuric patients. AIM: To examine whether ACEIs affect TIF, directly or indirectly. DESIGN: Prospective 3-year follow-up study. METHODS: We enrolled 49 patients with IgA nephropathy (IgAN), treating some with ACE inhibitors (n = 26, 1-2 mg/day temocapril or trandolapril) and some with calcium-channel blockers (CCB, n = 23, 2.5-5 mg/day amlodipine). Blood pressure, serum creatinine, and urinalysis were measured monthly, and 24-h endogenous creatinine clearance (CCr) at least once a year. RESULTS: In the CCB group, TIF was positively correlated with the rate of decline in CCr (dCCr), consistent with previous observations. In the ACEI group, dCCr was lower (0.02 +/- 0.02 vs. 0.06 +/- 0.03), and the TIF-dCCr correlation was absent. DISCUSSION: In the absence of post-treatment histological data, it is not possible to say whether ACEIs have an effect on TIF. However, ACEIs appear to slow the progression of renal failure in IgAN, regardless of the degree of TIF at presentation.     

Effect of isoproterenol on intracellular pH of the intercalated cells in the rabbit cortical collecting ducts.

To examine the mechanisms which regulate the functions of the intercalated cells (ICs) in the cortical collecting duct (CCD), the effect of isoproterenol on intracellular pH (pHi) of ICs was studied with the in vitro microperfused rabbit CCD, using the single cell pHi determination technique with fluorescent dye, 2',7'-bis-(2-carboxyethyl)-5(and-6)carboxyfluorescein. The pHi of beta-IC was significantly decreased with the addition of basolateral 10(-6) M isoproterenol (7.21 +/- 0.04 to 7.05 +/- 0.04), whereas alpha-IC did not show any change. This response of beta-IC to isoproterenol was dose-dependent and completely inhibited by the beta-blockers, atenolol or propranolol. The addition of forskolin or 8-Br-cAMP mimicked the effects of isoproterenol, suggesting that the activation of adenylate cyclase induced the decrease in pHi. The rate of pHi changes after the Cl- removal from the perfusate, which is considered to reflect the activity of luminal anion exchanger, was significantly higher with isoproterenol (0.032 +/- 0.009 pH unit/s) than that in the control (0.023 +/- 0.009 pH unit/s). The present studies provide direct evidence for the regulation of beta-IC function by beta-adrenergic receptor; and the luminal Cl-/HCO3- exchanger was considered to be stimulated by beta-agonist, directly.     

Sandwich immunoassay for intact human osteocalcin.

To overcome the problems of limited-region specificity associated with conventional radioimmunoassay (RIA), we developed a sandwich enzyme immunoassay (EIA) for intact human osteocalcin (hOC). For this EIA we used antibodies to the N- and C-terminal regions of hOC that were raised against an N-terminal 20-residue peptide and a C-terminal 7-residue peptide, both synthetic. Immunoassay profiles of tryptic digests of hOC and serum from patients with renal failure, fractionated by reversed-phase HPLC, facilitated direct demonstration of the region specificity of this method. A preliminary study of serum osteocalcin concentrations in patients with renal failure further confirmed this specificity, showing lower positive rates obtained by this method than by conventional RIA. The cross-reactivity data of hOC with bovine and rat osteocalcins by the sandwich method indicated its species specificity. These studies demonstrate the superior specificity of this sandwich EIA compared with conventional RIA and thus confirm its potential diagnostic superiority.