The role of heparin in the changes of lipid patterns during a single hemodialysis

The effects of heparin administered during dialysis on serum lipids and lipoproteins were evaluated by comparing dialysis with heparin and dialysis without heparin. Gabexate mesilate (GM), a synthetic proteinase inhibitor, was used as an anticoagulant during dialysis without heparin. In dialysis with heparin, significant increases were observed in free fatty acids (FFA), high-density lipoprotein cholesterol (HDL-C), and plasma lipolytic activity (PLA). Triglyceride (TG) was decreased reciprocally and the lipoprotein electrophoretic pattern was markedly modified. In contrast, in dialysis without heparin, no significant changes were observed in all parameters of lipid metabolism. These data suggest that dialysis induced changes in lipids are mainly caused by heparin and that acetate and glucose in dialyzate make an almost negligible contribution to abnormal lipid patterns in patients on maintenance hemodialysis.     

Thymic stroma-derived T cell growth factor (TSTGF): III. Its ability to promote T cell proliferation without stimulating interleukin 2- or 4-dependent autocrine mechanism

A thymic stroma-derived cell clone, MRL104.8a produced a T cell growth factor designated as thymic stroma-derived T cell growth factor (TSTGF). This factor that is distinct from previously described T cell growth factors such as interleukin (IL) 2 or 4 was capable of promoting the growth of IL2-dependent, antigen-specific helper T cell clones. While such growth promotion was induced without requirement of the relevant antigen and exogenous IL2, we further investigated whether it depended on activation of an IL2- or IL4-dependent autocrine mechanism. Helper T cell clones, 8-E and 8-5, were able to proliferate in response to stimulation with either antigen or TSTGF. 8-E and 8-5 produced IL2 and IL4, respectively, in cultures following antigenic stimulation, whereas neither IL2 nor IL4 activity was detected in cultures during TSTGF-induced proliferation. The proliferation of these helper T cell clones by antigenic stimulation was almost completely inhibited when anti-IL2 receptor or anti-IL4 antibody was added to the cultures. The addition of cyclosporin A (CsA) to cultures of 8-E and 8-5 clones together with antigen also resulted in the complete inhibition of cellular proliferation in association with the suppression of IL2 and IL4 production. In contrast, TSTGF-induced proliferation was not affected by addition of either type of antibody or CsA. These results indicate that TSTGF is a novel T cell growth factor that can exert its own growth-promoting effect without depending on an IL2- or IL4-operating autocrine mechanism.     

Binding parameters of valproic acid to serum protein in healthy adults at steady state.

Two hundred milligrams of valproic acid (VPA) was administered orally to seven healthy adults at 9:00 and 21:00 h for 5 consecutive days, including the morning dose on day 6. On the sixth day, blood samples were drawn at 0, 0.17, 0.33, 0.5, 0.75, 1, 1.5, 3, and 6 h after the morning dose. Binding of VPA to serum protein was evaluated by ultrafiltration, and total and unbound VPA concentrations were determined by fluorescence polarization immunoassay. Binding parameters of VPA to serum protein were calculated for each subject by the Scatchard analysis. The binding parameters obtained from seven subjects showed that the mean association constant (K) was 2.72 x 10(4) L/mol while the total number of binding sites (nPt) was 789 mumol/L. There were marked interindividual variations and the coefficient of variation was 42% for K and 28% for nPt. These results show that endogenous free fatty acids (FFAs) significantly reduce the binding affinity of VPA to serum albumin (p less than 0.05). In addition, they suggest the possibility that the primary binding sites for VPA can be strongly reduced by FFAs. Therefore, we consider that interindividual differences in binding parameters may be clinically important.     

Usefulness of 31P-MRS as a method of evaluating the viability of preserved and transplanted rat liver

We used phosphorus-31 magnetic resonance spectroscopy (³¹P-MRS) to evaluate the viability of transplanted rat liver. Wistar rats were used as donors and recipients. The donor livers were preserved in saline (group 1), Euro-Collins solution (group 2), or in University of Wisconsin (UW) solution (group 3) for 3 and 6 h in groups 1, 2 and 3 and for 9 h in groups 2 and 3. Thereafter the livers were orthotopically transplanted. ³¹P-MRS spectra were measured after portal reperfusion. Finally, all the recipients were divided into survivors and non-survivors. Survival rates were better in group 3 than in groups 1 and 2. In the 9-h-preserved livers, the livers in group 3 showed a significantly higher β-ATP/Pi ratio than those in group 2. Comparing survivors and non-survivors in the 6-h-preserved livers in group 2, survivors' livers showed significantly higher (3-ATP/Pi ratio than those of non-survivors. We concluded that ³¹P-MRS is a useful method for assessing viability of rat liver grafts.     

The production of denture by preform compression molding method. Part 2. Model material and fittability

A preform compression molding method to make polysulfone denture was reported previously by paper. Properties of the mold, adaptability of the molded denture to master model and the movement of artificial teeth were examined. It was necessary to raise the temperature of the crystbalite-stone model above 270 degrees C to obtain stable expansion. Mold made using 22 wt%-colloidal silica showed strong compressive strength under the compression molding condition. Displacement of artificial teeth between wax denture and polysulfone denture was independent of the mold expansion, and the displacement was equal to that of heat-curing acrylic denture. Adaptability of the molded denture to the master model was associated with expansion of the model. Good adaptability was obtained under the expansion of the model, such as setting expansion about 0.30% and total expansion 1.05-1.10%, with about 0.2 mm average discrepancy.     

Two types of DNA ligase I activity in lymphoblastoid cells from patients with Bloom's syndrome

DNA ligases I and II were separated by hydroxylapatite (HA) column chromatography in cell-free extracts of lymphoblastoid cell lines (LCLs) derived from two unrelated patients with Bloom's syndrome (BS) and two healthy individuals. The specific activity of ligase I from the crude extract was consistently lower in GM3403, a BS LCL from an Ashkenazi Jewish patient, than in normal control LCLs. By contrast, the level of ligase I activity in BSL-2KA, another BS LCL derived from a Japanese patient, was equivalent to those in normal LCLs, although GM3403 and BSL-2KA shared the feature of exceedingly high frequency of spontaneous sister-chromatid exchange. The levels of total ligase activity in crude extracts without the separation into the two forms, however, were approximately two-fold higher for the two BS LCLs than for the normal LCLs. Partial purification by chromatography on a DEAE-cellulose 23 column and a phosphocellulose column did not affect the superiority of the two BS LCLs over the normal LCLs in the specific activity of the total ligases. Nonetheless, subsequent application to an HA column again resulted in much less elevation of the specific activity of ligase I for GM3403 than for BSL-2KA and control LCLs. The levels of ligase II activity, accounting for 4-13% of total ligase activity, were similar among the LCLs examined. Irrespective of the extent of purification, essentially no difference in the heat lability of DNA ligase I was detected among the four LCLs. These findings suggest that there may exist among BS LCLs at least two types of subtle abnormality of DNA ligase I itself and/or a putative substance modulating the enzyme function.