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R Latza

Publications and source records attributed to R Latza.

At least 19 recordsLinked to original sources
PubMed2004

[Platelet reactivity index by Grotemeyer].

In 1974 Wu and Hoak described a method for determining circulating platelet aggregates. This method was modified by Grotemeyer in 1983. The platelet reactivity index (PR) is based on the ratio of platelet aggregates in blood samples obtained in different buffer solutions. Platelet aggregates are resolved, when blood is sampled in EDTA-buffer, but remain fixed when EDTA-formalin-buffer is used. Generally, the PR is preferred, because in vitro manipulations of platelets are not necessary, and the results are estimated automatically. PR values above 1.05 are suspicious for elevated platelet aggregation. PR values above 1.2 indicate pathological changes in platelet aggregation. The PR is inexpensive (4.0 D ) and rapid to perform. PR-values were used successfully to identify non-responders to secondary prophylaxis with acetylsalicylic acid (ASA), i. e. patients suffering from stroke (33%) and after cardiac ischaemia (18%). Furthermore, elevated PR-values correlated significantly with the incidence of arterial thromboembolic complications. The PR correlated well in a own prospective study (drug monitoring) with values received from the retention test Homburg (RT-H) and the platelet function analyser (PFA-100). These data indicate that the values of the PR seems to be highly predictive for the evaluation of the ASA therapy. However, the PR is not suitable for the determination of ASA overdosage.

Blood Platelets↗
PubMed2004

Blood fluidity, fibrinogen, and cardiovascular risk factors of occlusive arterial disease: results of the Aachen study.

In the Aachen study the prevalence of arterial disease was established in 346 out of a cohort of 2821 subjects between 45 and 65 years of age. Rheological variables and risk factor profile for patients with peripheral occlusive arterial disease (POAD), coronary heart disease (CHD) and cerebrovascular insufficiency (CI) in comparison to a control group are given. Significantly elevated are hematocrit in males, plasma viscosity, erythrocyte aggregation and fibrinogen. It is evident that plasma viscosity is the rheological parameter most often elevated in patients with arterial disease (70.8%). In patients with CI (80.6%) plasma viscosity is elevated about four times more often than in healthy subjects. While 85.8% of healthy volunteers show no or only one elevated rheological parameter only 44.5% of the patients have this constellation. Risk factors are bundled in patients compared to healthy volunteers. 84.2% of the healthy volunteers have no or only one risk factor whereas patients with OAD show this constellation in only 30.9% (32.4% in POAD, 16.1% in CI and 32.4% in CHD).

Blood Viscosity↗
PubMed2001

Current topics on low-density lipoprotein apheresis.

The prognosis of patients suffering from severe hyperlipidemia, sometimes combined with elevated lipoprotein (a) (Lp[a]) levels, and coronary heart disease (CHD) refractory to diet and lipid-lowering drugs is poor. For such patients, regular treatment with low-density lipoprotein (LDL) apheresis is the therapeutic option. Today, there are four different LDL-apheresis systems available: immunoadsorption, heparin-induced extracorporeal LDL/fibrinogen precipitation, dextran sulfate LDL-adsorption, and LDL-hemoperfusion. Despite substantial progress in diagnostics, drug therapy, and cardiosurgical procedures, atherosclerosis with myocardial infarction, stroke, and peripheral cellular disease still maintains its position at the top of morbidity and mortality statistics in industrialized nations. Established risk factors widely accepted are smoking, arterial hypertension, diabetes mellitus, and central obesity. Furthermore, there is a strong correlation between hyperlipidemia and atherosclerosis. Besides the elimination of other risk factors, in severe hyperlipidemia (HLP) therapeutic strategies should focus on a drastic reduction of serum lipoproteins. Despite maximum conventional therapy with a combination of different kinds of lipid-lowering drugs, however, sometimes the goal of therapy cannot be reached. Mostly, the prognosis of patients suffering from severe HLP, sometimes combined with elevated Lp(a) levels and CHD refractory to diet and lipid-lowering drugs is poor. Hence, in such patients, treatment with LDL-apheresis can be useful. Regarding the different LDL-apheresis systems used, there were no significant differences with respect to the clinical outcome or concerning total cholesterol, LDL, high-density lipoprotein, or triglyceride concentrations. With respect to elevated Lp(a) levels, however, the immunoadsorption method seems to be the most effective. The published data clearly demonstrate that treatment with LDL-apheresis in patients suffering from severe hyperlipidemia refractory to maximum conservative therapy is effective and safe in long-term application.

Coronary Artery Disease↗
PubMed2000

Low density lipoprotein apheresis in treatment of hyperlipidemia: experience with four different technologies.

The prognosis of patients suffering from severe hyperlipidaemia (HLP), sometimes combined with elevated lipoprotein (a) levels, and coronary heart disease (CHD) refractory to diet and lipid lowering drugs is poor. A new therapeutic option for such patients is regular treatment with low density lipoprotein (LDL) apheresis. In total 33 patients (16 males, 17 female, aged 43.8+/-14.3 years), suffering from severe HLP resistant to diet and lipid lowering drugs, were treated for 62.3+/-21.3 (range, 1-113) months with LDL-apheresis. Four different LDL-apheresis systems were used: the dextran sulfate adsorption for 28 of 33 (Liposorber, Kaneka, Japan), immunoadsorption for 2 of 33 (Therasorb, Baxter, Germany), LDL-hemoperfusion for 2 of 33 (Dali, Fresenius, Germany), and the immunoadsorption system with special antilipoprotein (a) columns for 1 of 33 patients (Lipopak, Pocard, Russia). Before applying LDL-apheresis, 27 of 33 patients suffered from CHD with severe angina pectoris symptoms, a history of myocardial infarction or coronary artery venous bypass (CAVB). With LDL-apheresis, reductions (p < 0.05) of 46% for total cholesterol, 49% for LDL, 28% for Lp(a), and 38% for triglycerides were reached. Severe side-effects, such as shock or allergic reactions, were very rare (0.5%). In the course of treatment an improvement in general well-being and increased performance were experienced in 29 of 33 patients. In 23 of 27 patients suffering from CHD, a reduction of 60 to 100% of nitrate medication was observed. Regarding the different apheresis systems used, there were no significant differences with respect to the clinical outcome and concerning total cholesterol, LDL, HDL, and triglyceride concentrations. But, in respect to elevated lipoprotein (a) levels, the immunoadsorption method using special anti-lipoprotein (a) columns seems to be the most effective (-57% versus -25% [Kaneka, p < 0.05] or -23% [Baxter, p < 0.05]). The present data clearly demonstrate that treatment with LDL-apheresis in patients suffering from severe HLP, refractory to maximum conservative therapy, is effective and safe in long-term application.

Adult↗
PubMed2000

Therapeutic plasma exchange in treatment of adrenoleukodystrophy.

Adrenoleukodystrophy (ALD) is an X-linked disorder of metabolism of very long-chain fatty acids (VLCFA) with a frequency of up to 1:20,000 in males. VLCFA C 24:0 and C 26:0 accumulate in the cholesterol ester and ganglioside fraction in plasma and red cells. Symptoms of ALD are ataxia, loss of visual and auditory functions, and cerebral convulsions. Presently, no sure therapeutic approaches are established. Efforts were reported by dietary regimens with VLCFA-restriction and glycerol trioleate and glycerol trierucate intake. In the present trial, we report on a 58-year-old white male suffering from progressive ALD with spastic paraparesis. He has a positive family history back to the 18th century. In this patient, although maximum dietary therapy was applied over a period of 60 months, no normalization of VLCFA C24:0 and C26:0 was reached, and neurological disorders were progressive. As a result, therapeutic plasma exchange (TPE) was applied from 1990 to 1994. Then, for more selective adsorption of VLCFA, dextran-sulfate adsorption (Liposorber, Kaneka, Osaka, Japan) until 1996, and after that, immunoadsorption (Therasorb, Baxter, Munchen, Germany) were used. During these periods (total, 101 months), VLCFA C 24:0 and C 26:0 levels were reduced by 55% and 50% (p < 0.001). The patient experienced a significant improvement in performance and general well-being. No further progression of neuronal disorders was documented. This anecdotal data suggest a very beneficial effect of TPE in treatment of progressive ALD.

Adrenoleukodystrophy↗
PubMed2000

Surface treated catheters with ion beam based process for blood access.

Infection, thrombosis, and stenosis are among the most frequent complications associated with blood contacting catheters. Because these problems are usually related to surface properties of the base catheter material, surface treatment processes such as ion implantation and ion beam assisted deposition (IBAD) (silver based coatings) can be used to mitigate such complications. Because these ion beam based processes affect only the near-surface region (approximately the outer 1 microm), there is little effect on bulk material properties. This study evaluated silver coated large bore catheters used for extracorporeal detoxification. In a 135 patient prospective study, 170 large bore catheters were inserted into the internal jugular or subclavian veins. Seventy-eight surface treated catheters (Spi-Argent, Spire Corporation, Bedford, MA, U.S.A.; n = 32 acute catheters, n = 46 long-term catheters) were inserted in 55 patients. Ninety-two untreated catheters placed in 80 patients served as controls (n = 40 acute catheters, n = 52 long-term catheters). After removal, the catheters were cultured for bacterial colonization using standard microbiologic assays. They also were examined using a scanning electron microscope (SEM). Bacterial colonization was observed in 7% of the treated catheters compared with 35.3% of untreated catheters. The SEM investigations showed all treated catheters to possess low thrombogenicity. Results of the study indicate that ion beam based processes can be used to improve thrombus and infection resistance of blood contacting catheters.

Adult↗
PubMed2000

Hypervolumetric hemodilution with HES 100/0.5 10% in patients with peripheral arterial occlusive disease (Fontaine, stage II): an open clinical and pharmacological phase IV study.

The efficacy of three weekly interventions with hypervolumetric hemodilution of a new preparation of hydroxyethyl starch (HES 100/0.5, 10%, C2/C6 substitution ratio of 6.5) on pain-free walking distance of patients with peripheral arterial occlusive disease (PAOD) stage IIb on the Fontaine classification was investigated. In addition quantitative data on the pharmacokinetic properties of this HES preparation, and it's impact on hemorheology, hemostasis and homeostasis were shown. Ten patients were included according to a predefined protocol, and treated openly with 500 ml HES 100/0.5 10% on nine occasions over 18 days. Pain-free walking distance, the main outcome measure, showed a mean increase of 82 m (+60%). Hematocrit decreased 4 percentage points on average (5.5 percentage points one hour after interventions). Plasma viscosity dropped 5% on average with significant changes immediately after interventions only in patients whose baseline values had been equal to or above the 2 s reference area. Erythrocyte aggregation decreased by 16% in the course of treatment (8% immediately after interventions), systolic blood pressure by 13%, and total protein by 7%. Complement showed a trend towards lower values (-20%), and creatinine, pH and urine viscosity remained unchanged. Apart from complement changes, all reductions mirrored the dilution effects. As to pharmacokinetics, serum mean molecular weight distribution was very similar to that of the infusion. A minor adverse drug reaction (light, spontaneously disappearing pruritus) was observed in one case.

Aged↗
PubMed2000

Capillary microscopic and rheological dimensions for the diagnosis of von Willebrand disease in comparison to other haemorrhagic diatheses.

It is known that angiodysplasia influence macrocirculation as well as microcirculation in patients with vWD. In the present study it was examined if intravital capillary microscopic dimensions (morphologic and dynamic) in skin (nailfold) in combination with rheologic parameters could give indications for the presence of vWD in patients with haemorrhagic diathesis. Patients with vWD (n = 100; 92 type 1: definite type 1:78 and possible type 1:14: 8 type 2A) have in comparison to patients with other haemorrhagic diathesis [thrombocytopathy (n = 122), thrombocytopenia (n = 101). severe haemophilia A (n = 50) and severe haemophilia B (n = 20). congenital dysfibrinogenaemia (n = 22), oral anticoagulation with phenprocoumone (n = 112)] and to apparently healthy subjects (n = 100) a significantly increased capillary torquation (median index: 3.5), a venolar and an arteriolar capillary dilatation (median: 16.5 microm; median: 15.1 microm) and the highest part of microscopic bleedings (extravasates) with 40% in the video capillary microscopy as morphological changes. Only the congenital dysfibrinogenaemia appears with a larger dilatation in venolar capillaries (median: 14.5 microm). Microscopic bleedings are much less common in other haemorrhagic diatheses with a frequency between 4% and 13%. In the vWD a significantly reduced duration of reactive hyperaemia (median: 150 sec). This is the only dynamic change that can be taken as a possible hint for a loss of flexibility within the precapillary vessels. A significantly reduced plasma viscosity (< 1.25 mPas) is typical for the vWD due to the increase of the shear stress in blood plasma because of the reduction of vWF-activities. Changes of the capillary morphology (dilatation, extravasates, capillary torquation) and the hypoplasmaviscosity are most sensitive for the vWD (75%, 65%, 40%, 80%) with a fairly high specifity (up to 93%) and a positive predictive value of 99%. As a conclusion it seems reasonable to discuss the introduction of video capillary microscopy as a screening test for haemostasiological and angiological centers.

Adult↗
PubMed1999

The antiatherosclerotic effect of Allium sativum.

In a randomized, double-blind, placebo-controlled clinical trial, the plaque volumes in both carotid and femoral arteries of 152 probationers were determined by B-mode ultrasound. Continuous intake of high-dose garlic powder dragees reduced significantly the increase in arteriosclerotic plaque volume by 5-18% or even effected a slight regression within the observational period of 48 months. Also the age-dependent representation of the plaque volume shows an increase between 50 and 80 years that is diminished under garlic treatment by 6-13% related to 4 years. It seems even more important that with garlic application the plaque volume in the whole collective remained practically constant within the age-span of 50-80 years. These results substantiated that not only a preventive but possibly also a curative role in arteriosclerosis therapy (plaque regression) may be ascribed to garlic remedies.

Adult↗
PubMed1998

Low frequency electrorotation of fixed red blood cells.

Electrorotation of fixed red blood cells has been investigated in the frequency range between 16 Hz and 30 MHz. The rotation was studied as a function of electrolyte conductivity and surface charge density. Between 16 Hz and 1 kHz, fixed red blood cells undergo cofield rotation. The maximum of cofield rotation occurs between 30 and 70 Hz. The position of the maximum depends weakly on the bulk electrolyte conductivity and surface charge density. Below 3.5 mS/m, the cofield rotation peak is broadened and shifted to higher frequencies accompanied by a decrease of the rotation speed. Surface charge reduction leads to a decrease of the rotation speed in the low frequency range. These observations are consistent with the recently developed electroosmotic theory of low frequency electrorotation.

Biophysical Phenomena↗
PubMed1998

Early rheological and microcirculatory changes in children with type I diabetes mellitus.

In order to determine early changes in microcirculation and hemorheological parameters in diabetics, a cross-sectional study was carried out with 273 children with diabetes mellitus type I during their vacation in a state country convalescent home for diabetic children and teenagers in Kaiserslautern. Compared to healthy children, typical changes of hemorheological variables as well as in the microcirculation of the skin and retina are observed in poorly controlled diabetic children. Morphological changes are obvious in capillary areas in form of marked capillary contortions and dilatations of venous branches, rigid erythrocytes, and hyperaggregable thrombocytes. An effort should be undertaken to normalize the pathologically changed parameters of blood fluidity and the microcirculation by an adequate control of blood glucose, and possibly by changes in dietary habits.

Adolescent↗
PubMed1997

Cyclosporin and plasmapheresis in treatment of progressive systemic lupus erythematosus (pSLE).

The prognosis of patients suffering from progressive systemic lupus erythematosus (pSLE) is poor, despite treatment with intensive drug regimens with combinations of corticosteroids, azathioprine and cyclophosphamide. Side-effects such as infections and malignomas often occur. In the present trial, 21 patients (four male, 17 female, aged 37.9 +/- 12.8) suffering from pSLE for 9.4 +/- 2.6 years, were treated for 2.3 +/- 1.8 years with drug regimens as mentioned above. Then, over a period of 6.4 +/- 2.6 (range 1-8) years, in addition to conventional therapies, cyclosporin (2.5 +/- 0.6 mg/kg body wt/d) and, in active stages of the disease with extremely high concentrations of anti-ds-DNA-, anti-nuclear antibodies and circulating immunocomplexes, plasmapheresis (therapeutic plasma exchange (TPE)) have been applied. Compared with previous treatment modalities, significantly (P < 0.05) more effective and rapid reduction of antibodies was achieved. Clinical symptoms improved within 2 to 4 weeks. Under the new therapeutic regimen all patients reported increased performance and a better quality of life. After 5 to 48 (17.5 +/- 13.8) months, cyclosporin was established as mono-therapy for 8/21 patients. In] the other cases, corticosteroids, azathioprine and cyclophosphamide were reduced by 40 to 100%. No severe side-effects were seen. In acute stages of pSLE and in forms with persistently high antibody levels, the addition of TPE to conventional therapy was very effective, with regard to improving both clinical and laboratory parameters.

Adolescent↗
PubMed1997

Cyclosporine and therapeutic plasma exchange in treatment of progressive autoimmune diseases.

Despite treatment with intensive immunosuppressive drug regimens, the prognosis of patients suffering from severe progressive autoimmune diseases like systemic lupus erythematosus (SLE), nephrotic syndrome (NS), and Behçet's disease is poor. Side effects (infections and malignant tumors) often occur. In the present trial, 35 patients suffering from autoimmune diseases (SLE, n = 21; NS, n = 10; and Behçet's disease, n = 4) were treated for 3.7 +/- 2.0 years with 2.5 +/- 0.6 mg cyclosporine/kg body weight/day in addition to corticosteroids alone or in combination with azathioprine and/or cyclophosphamide. In active stages of the diseases with extremely high concentrations of anti-ds-DNA-antibodies, antinuclear antibodies, circulating immunocomplexes, and reduced complement concentrations, therapeutic plasma exchange (TPE) has been applied. Compared with previous treatment modalities, significantly (p < 0.05) more effective and rapid reductions of the antibodies were reached. Clinical disorders improved within 1-6 weeks. All patients reported increased performance and a better quality of life. After 1-12 months, the previously required doses of immunosuppressive drugs and the frequency of TPE could be reduced by 40-100%. After 13.4 +/- 11.8 months in 17 of 35 patients (8 with SLE, 5 with NS, 4 with Behçet's disease), cyclosporine was established as the monotherapy. No severe side effects were registered. In treating active stages of severe progressive autoimmune diseases and forms with persistent high antibody levels, the addition of TPE to conventional therapy was very effective, as observed in both clinical and laboratory parameters.

Adrenal Cortex Hormones↗
PubMed1997

LDL apheresis in clinical practice: long-term treatment of severe hyperlipidemia.

Thirty patients (13 males, 17 females) suffering from familial hypercholesterolemia resistant to diet and lipid-lowering drugs were treated for 48.7 +/- 19.2 months (range, 2-87 months) with low density lipoprotein (LDL) apheresis. Three different systems (dextran sulfate adsorption for 27 of 30 [Kaneka, Liposorber, Japan], immunoadsorption system for 2 of 30 [Baxter, Therasorb, Germany], immunoadsorption system with special lipoprotein a [Lp(a)] columns for 1 of 30 patients [Lipopak, Pocard, Russia]) were applied. Before LDL apheresis 24 of 30 patients suffered from coronary heart disease (CHD) with angina symptoms. With LDL apheresis, reductions of 46% for total cholesterol, 49% for LDL, 30% for Lp(a), and 38% for triglycerides were reached. Severe side effects such as shock or allergic reactions were very rare (0.5%). In the course of treatment, an improvement in general well-being and increased performance were experienced in 27 of 30 patients. A 60 to 100% reduction of nitrate medication was observed in 17 of 24 patients. Regarding the different apheresis systems used, at the end of the trial there were no significant differences with respect to the clinical outcome experienced by the patients and concerning total cholesterol, LDL, high density lipoprotein, and triglyceride concentrations. But to reduce high Lp(a) levels, the immunoadsorption method with special Lp(a) columns seems to be the most effective (-57% versus 25% [Kaneka] and 23% [Baxter]). The present data clearly demonstrate that treatment with LDL apheresis of patients suffering from familial hypercholesterolemia, resistant to maximum conservative therapy, is very effective and safe, even in long-term application.

Adult↗
PubMed1997

Plasmapheresis in treatment of adrenoleukodystrophy.

Adrenoleukodystrophy (ALD) is an X-linked disorder of metabolism of very long chain fatty acids (VLCFAs) with a frequency of up to 1:20,000 in males. VLCFAs C24:0 and C26:0 accumulate in the cholesterol ester and ganglioside fraction in plasma and red cells. Symptoms of ALD are ataxia, loss of visual and auditory functions, and cerebral convulsions. Up to the present, no sure therapeutic approaches have been established. Efforts were reported by dietary regimens with VLCFA restriction and glyceroltrioleate and glyceroltrierucate intake. In the present trial, we report a 55-year-old Caucasian male suffering from progressive ALD with spastic paraparesis. He has had a positive family history since the eighteenth century. In this patient treated with maximum dietary therapy over a period of 60 months, no normalization of C24:0 and C26:0 was reached, and neurological disorders were progressive. As a result, plasmapheresis was applied during the period 1990-1994 and since then for more selective adsorption of VLCFAs, dextran sulfate adsorption (Liposorber, Kaneka, Japan). During this period (64 months), C24:0 and C26:0 levels were reduced by 54.5% and 51.8%, respectively (p = 0.0001). The patient experienced a significant improvement in performance and general well-being. There has been no further progression of neuronal disorders to document.

Adrenoleukodystrophy↗
PubMed1996

Low-density lipoprotein-apheresis in two patients with extremely elevated lipoprotein (a) levels.

Two male caucasian patients (36 and 42 years old) with heterozygous familial hypercholesterolemia and extremely elevated lipoprotein Lp(a) concentrations, resistant to diet and lipid-lowering drugs, were treated with low-density lipoprotein (LDL)-apheresis for 55 months (liposorber system, Kaneka, Japan) and 15 months (immunoadsorption system, special Lp(a) columns, Lipopak, Pocard, Russia). Lp(a) dropped on average by 50%, total cholesterol by 27%, LDL-cholesterol by 42%, triglycerides by 43%, and the fibrinogen concentration by 16%.

Adult↗