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J Dräger

Publications and source records attributed to J Dräger.

9 recordsLinked to original sources
PubMed2002

Direct adsorption of low-density lipoprotein and lipoprotein(a) from whole blood: results of the first clinical long-term multicenter study using DALI apheresis.

Direct adsorption of lipoproteins (DALI) is the first low-density lipoprotein (LDL)-apheresis technique by which atherogenic LDL and lipoprotein(a) (Lp(a)) can be selectively removed from whole blood without plasma separation. The present study was performed to evaluate the efficacy, selectivity and safety of long-term DALI apheresis. Sixty-three hypercholesterolemic coronary patients were treated by weekly DALI sessions. Initial LDL-cholesterol (C) plasma levels averaged 238 +/- 87 mg/dl (range 130-681 mg/dl). On average, 34 sessions (1-45) were performed processing 1.5 patient blood volumes. The primary aim was to acutely reduce LDL-C by >or=60% per session. To this end, three different adsorber sizes could be employed, i.e., DALI 500, 750, and 1000, which were used in 4, 73, and 23% of the 2156 sessions, respectively. On average, 7387 ml of blood were processed in 116 min per session. This resulted in the following mean acute changes: LDL-C 198 --> 63 mg/dl (-69%), Lp(a) 86 --> 32 mg/dl (-64%), triglycerides 185 --> 136 mg/dl (-27%). HDL-C (-11%) and fibrinogen (-15%) were not significantly influenced. The mean long-term reduction of LDL-C was 42% compared to baseline while HDL-C slightly increased in the long run (+4%). The selectivity of LDL removal was good as recoveries of albumin, immunoglobulins, and other proteins exceeded 85%. Ninety-five percent of 2156 sessions were completely uneventful. The most frequent adverse effects were hypotension (1.2% of sessions) and paresthesia (1.1%), which were probably due to citrate anticoagulation. Access problems had to be overcome in 1.5%, adsorber and hardware problems in 0.5% of the sessions. In this multicenter long-term study, DALI apheresis proved to be an efficient, safe, and easy procedure for extracorporeal LDL and Lp(a) elimination.

Adsorption↗
PubMed2000

Strong anomaly in diffusion generated by iterated maps.

We investigate the diffusion generated deterministically by periodic iterated maps that are defined by x(t+1) = x(t)+ax(z)(t)exp[-(b/x(t))(z-1)], z>1. It is shown that the obtained mean squared displacement grows asymptotically as sigma(2)(t) approximately ln (1/(z-1))(t) and that the corresponding propagator decays exponentially with the scaling variable |x|/square root of (sigma(2)(t))]. This strong diffusional anomaly stems from the anomalously broad distribution of waiting times in the corresponding random walk process and leads to a behavior obtained for diffusion in the presence of random local fields. A scaling approach is introduced which connects the explicit form of the maps to the mean squared displacement.

Journal Article↗
PubMed2000

DALI apheresis in hyperlipidemic patients: biocompatibility, efficacy, and selectivity of direct adsorption of lipoproteins from whole blood.

Recently, the first apheresis technique for direct adsorption of low-density lipoprotein (LDL) and lipoprotein(a) [Lp(a)] from whole blood (DALI) was developed that does not require a prior plasma separation. That markedly simplifies the extracorporeal circuit. The aim of the present study was to test the acute biocompatibility, efficacy, and selectivity of DALI apheresis. In a prospective clinical study, 6 hypercholesterolemic patients suffering from angiographically proven atherosclerosis were treated 4 times each by DALI. 1.3 patient blood volumes were treated per session at blood flow rates of 60-80 ml/min using 750 or 1,000 ml of polyacrylate/polyacrylamide adsorber gel. The anticoagulation consisted of an initial heparin bolus followed by a citrate infusion. The sessions were clinically essentially uneventful. Mean corrected reductions of lipoproteins amounted to 65% for LDL-cholesterol, 54% for Lp(a), 28% for triglycerides, 1% for HDL-cholesterol, and 8% for fibrinogen. The selectivity of lipoprotein removal was high. Cell counts remained virtually unchanged and no signs of hemolysis or clotting were detected. Cell activation parameters elastase, beta-thromboglobulin, interleukin-1beta, and IL-6 showed no significant increase. Complement activation was negligible. There was significant, but clinically asymptomatic, bradykinin activation in the adsorber with mean maxima of 12,000 pg/ml in the efferent line at 1,000 ml of treated blood volume. In conclusion, DALI proved to be safe, selective, and efficient for the adsorption of LDL-C and Lp(a), which simplifies substantially the extracorporeal therapy in hypercholesterolemic patients.

Acrylic Resins↗
PubMed1999

Sorting single events: mean arrival times of N random walkers.

Using a scaling approach we investigate the first passage time < mu(1,N)(r)> for the first out of N identical independently diffusing particles in ordered and disordered structures. For Euclidean spaces we obtain < mu(1,N)(r)> in terms of a series in (ln N)(-1), independent of dimension. In the case of disordered ramified fractals < mu(1,N)(r)> is expressed in terms of a series in (ln N)((1-d(l)(w))), where d(l)(w) describes how the mean topological distance evolves with time t. We propose a scaling behavior for the related quantity S(N)(t), the number of distinct sites visited by N particles. We verify our predictions by numerical simulations.

Journal Article↗
PubMed1983

Effects of DDT and dieldrin on intestinal glucose transport and brush border hydrolases. A comparison with phenobarbital and methylcholanthrene.

The enhancement of in vitro small intestinal transcellular glucose transport in NMRI mice after oral administration of the organic pesticides 2,4-DDT and dieldrin can be shown to be due to an increased active transport at the site of the brush border membrane. Intestinal disaccharidase activities were concomitantly elevated in the dieldrin group, while DDT produced no effects with intestinal hydrolases. The classic enzyme inducing agents phenobarbital and methylcholanthrene failed to stimulate intestinal glucose transport, although both increased intestinal disaccharidase activities considerably, thus questioning a close relation between these digestive and absorptive functions in the translocation of glucose. Intestinal alkaline phospatase activity was enhanced after DDT, dieldrin and methylcholanthrene treatment, but not with phenobarbital. It is suggested that DDT and dieldrin exert their stimulating effect on intestinal glucose transport by a mechanism different from general induction of metabolic pathways.

Animals↗