Biomedical subjects
Publications and source records attributed to H Achenbach.
Up to 21% of severe cases of malaria tropica are associated with polyuria and are life-threatening. We describe a 39-yr-old man with malaria tropica who developed disseminated intravascular coagulation, polyuria, and a pituitary lesion. Empiric treatment with vasopressin improved the polyuria. This is the first case of malaria tropica in which central diabetes insipidus has been documented.
Anemia is as a frequent complication in patients with chronic kidney disease, which gains in importance in the treatment of patients with renal disease. The main cause of renal anemia is the inadequately low production of endogenous erythropoietin. Often the patients develop an additional absolute or functional iron deficiency, which complicates the diagnostic and therapeutic procedures. Substitution of recombinant human erythropoietin (r-HuEPO) is the most effective therapy. The goal is a stable haemoglobin level >11 g/dl. An often additional existing iron deficiency should be balanced adequately according to the guidelines. With consequent and early treatment morbidity, mortality, and quality of life can be effectively improved.
A 32-year-old male patient presented in the emergency department of our hospital with acute vomiting and diarrhoea. He reported occasional non-severe diarrhoea over several years in the past. Furthermore, at the time of presentation the patient had had anuria for several days. A prerenal and postrenal origin of the renal failure was excluded. A renal biopsy was performed and histopathological examination displayed findings consistent with a haemolytic-uraemic syndrome but no signs of glomerulonephritis. MRI examination of the small bowel revealed inflammatory alterations typical for Crohn's disease, even without histological verification. We describe haemolytic-waemic syndrome as manifestation of Crohn's disease for the first time.
The pharmacokinetics of the low-molecular weight heparin (LMWH), dalteparin, was evaluated after a single intravenous bolus injection of 50 IU anti-Xa/kg in 8 healthy volunteers, 8 patients with moderate/severe renal failure (Cl(crea) 13.1-56.5 ml/min) and 8 hemodialysis patients. Venous blood samples were taken over a 1-day period to determine anti-Xa activity, anti-IIa activity and plasma levels of free tissue factor pathway inhibitor (free TFPI). Plasma anti-Xa and anti-IIa activities were measured using chromogenic assays and free TFPI levels using an ELISA technique. The anti-Xa clearance was significantly decreased (p < 0.05) in both groups with renal insufficiency when compared with healthy volunteers. There was a positive correlation between creatinine clearance and anti-Xa clearance in the healthy volunteers and patients with moderate/severe renal failure. The anti-Ila activity was characterized by 3- to 4-fold lower plasma concentrations and faster elimination compared with the anti-Xa activity. In patients with moderate/severe renal failure the elimination of anti-lla was only slightly decreased, whereas in hemodialysis patients anti-Ila clearance was significantly decreased (p < 0.01). There was no correlation between creatinine clearance and anti-IIa clearance. The baseline mean free TFPI plasma levels in the two groups with renal insufficiency were significantly higher (p < 0.01) than in healthy volunteers. Dalteparin administration induced a transient, 6.0- to 8.1-fold increase in the free TFPI values in the three study groups. Dalteparin induced an increase in C(max) and AUC(0 - infinity) values of free TFPI in the two groups with renal insufficiency that was higher than in healthy volunteers. No bleeding complications occurred during the study. In conclusion, this is the first report showing retarded elimination of dalteparin and enhanced free TFPI plasma levels induced by a LMWH in patients with renal insufficiency.
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A more detailed phytochemical analysis of extracts of the aerial parts of Spigelia anthelmia L. (Loganiaceae) yielded 20 structurally related new compounds besides spiganthine and ryanodine. Structure elucidation was achieved mainly by spectroscopic methods. The compounds were tested on their cardiac and on their insect antifeedant activities.
This is a case report of a 36 years old man who has been suffering for 20 years from benign recurrent intrahepatic cholestasis (BRIC). BRIC is a rare autosomal recessive disease characterised by prolonged episodes of intrahepatic cholestasis and pruritus alternating with periods of nearly normal liver function, and does not progress to cirrhosis. Since all former approaches to medical treatment of the patients severe pruritus were ineffective, the patient was treated by 3 sessions of albumin dialysis (MARS, Molecular Adsorbents Recirculating System). MARS dialysis decreased serum bilirubin levels by more than 60 % and effectively lowered serum bile acid levels by 45 %. The course of serum parameters was accompanied by a dramatic clinical improvement of the patients symptoms (pruritus, jaundice, fatigue etc.). MARS therapy appeared to shorten the duration of the cholestatic attack.
OBJECTIVE: The objective of this study was to investigate the effect of renal impairment on the pharmacokinetics of the selective beta1-receptor antagonist talinolol. METHODS: Pharmacokinetic data were obtained in 12 healthy volunteers, 12 patients with renal impairment and 8 patients with terminal renal insufficiency after the oral administration of 100 mg talinolol and under steady state conditions (100 mg talinolol daily). Concentrations of talinolol in plasma, urine and dialysate during hemodialysis were measured with a validated HPLC-method. RESULTS: Talinolol is absorbed quite rapidly from the gastrointestinal tract (tmax 2.5-4 h). Steady state conditions were reached within 3-4 days depending on renal function. The calculated mean elimination half-life (t(1/2z)) in healthy volunteers (11 male, 1 female) was about 12 h. After an oral dose of 100 mg, about 55% of the bioavailable talinolol is eliminated unchanged in the urine. This fraction is reduced to 25% in patients with moderate to severe renal failure. A strong correlation was found between the renal elimination of talinolol and creatinine clearance. In patients with renal failure, the delayed elimination leads to an increase in t(1/2z) and to a decrease in the apparent total body clearance. Steady state trough levels (c(min)ss) in these patients are about 2.2-fold higher than in volunteers. The hemodialysability of talinolol was low. CONCLUSION: The disposition of talinolol shows a strong dependence on the renal function. On the basis of the kinetic data for talinolol, dose reductions of 30-50% are recommended in subjects with moderate to severe renal impairment.
Two new aporphinoid alkaloids, f1ttowianthine and 11-methoxylettowianthine were isolated from the root bark of Lettowianthus stellatus, together with the new sesquiterpene 11-hydroxyguaia-4,6-diene and the known compounds liriodenine, (Z)-7-octadecen-9-ynoic acid, methyl (2E,6E,10R)-10,11-epoxy-3,7,11-trimethyl-2,6-dodecadienoate, methyl (2E,6E,10R)-10,11-dihydroxy-3,7,11-trimethyl-2,6-dodecadienoate , and 3,4,5-trimethoxyphenol. The structure elucidation was achieved by spectroscopic methods.
In this work, we have studied the antifeedant and insecticidal effects of several natural ryanoid diterpenes. These compounds can be classified in two groups according to their chemical structures: ryanodol/isoryanodol-type (nonalkaloidal type) and ryanodine-type (alkaloidal type) ryanoids. The nonalkaloidal ryanoids were isolated from Persea indica (Lauraceae) while the alkaloidal ryanoids (ryanodines and spiganthines) were isolated from Spigelia anthelmia (Loganiaceae). The effects of these compounds on the feeding behavior and performance (with and without piperonyl butoxide pretreatment) of Spodoptera littoralis larvae and Leptinotarsa decemlineata adults indicate that some strongly deterred these insects, L. decemlineata being less sensitive than S. littoralis. Their antifeedant effects did not parallel their toxic action. Additionally, more than 60% of the nonalkaloidal ryanoids were antifeedants and/or toxic in contrast to 30% of active alkaloidal ones, supporting the hypothesis of a ryanodol-specific mode of action in insects.
Continuous ambulatory peritoneal dialysis (CAPD) has become an established procedure and is an equal alternative to haemodialysis (HD) in the management of terminal renal failure. Nevertheless CAPD still plays a minor role compared with HD (10% of all dialyses). CAPD offers advantages in quality of live but is still associated with a significant number of complications. The improvement of surgical technique and development of new peritoneal dialysis catheters (PDK) improved the results of peritoneal dialysis. 3 methods for implantation of PDK are used: the open surgical technique, the blind percutaneous procedure and the laparoscopic method. The latter technique is currently an accepted practice. 10 patients were treated by the laparoscopic method. Additionally to the PDK-tunnel of the abdominal wall we used 2 trocars (1 x 5 mm, 1 x 12 mm). Advantages of this technique are avoiding of perforating lesions, possibility for further operations and a safe implantation of the PDK. Peritoneal dialysis was started 7 days after operation with initially low dialysate volumes. The observed incidence of complications and removed catheters are comparable to the reports in the literature.
Modulatory effects of octopamine on ionic currents and spiking in isolated cockroach dorsal unpaired median neurons were investigated by means of the chopped voltage-/current-clamp and the patch-clamp technique. Octopamine increased the spiking frequency at concentrations < or = 10 microM and reduced it at > 10 microM. It enhanced a low voltage-activated Ca2+ current at 1 to 100 microM. At concentrations up to 10 microM two components of Ca2+-activated K+ current were potentiated. At > 10 microM octopamine in addition reduced a high voltage-activated Ca2+ current and the Ca2+-activated K+ current. A membrane permeant cAMP-analogue imitated the effects obtained at high octopamine concentration. Octopamine and cAMP in addition reduced a depolarizing resting current at both low and high concentration. Possible mechanisms and physiological significance are discussed for the opposite effects of octopamine observed at low versus high concentrations.
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From the methanolic extract of the roots of Tribulus cistoides the cardioactive saponin-3, which is known to occur in the leaves, was isolated along with tribulosin, a pregnane-type glycoside and eight new cholestane glycosides. D-(+)-Pinitol and sucrose were major constituents. The structures were established by spectroscopic studies of the isolated compounds, their acetylated derivatives and their hydrolysation products. Chemical conversions revealed the configurations at C-22 and C-25, respectively.
Spiganthine [1] was isolated as the main cardioactive principle from medicinally used extracts of Spigelia anthelmia. Its structure was established by spectroscopic methods. The biological effect of spiganthine is characterized by a delay in contraction development of the heart muscle.
Unlike the other former Soviet-block countries, Eastern Germany/the "GDR", had the opportunity to the re-unification with a highly developed western country, the Federal Republic of (West) Germany in 1990. In order to record the following rapid improvements in renal replacement therapy, we performed our own survey in Eastern Germany--excluding Eastern Berlin--by questionnaire, comparing the years 1989/December, and 1994/December. 112 of the 113 dialysis facilities for adult regular dialysis patients replied to our questionnaire (99%). From 1989 to 1994, the number of dialysis centers increased from 53 to 113 (-->213%), reaching 7.9 centres p.m.p. Of these facilities, 29% were hospital centers, 48% were private dialysis units, and 23% were run by nonprofit dialysis organizations. The number of dialysis stations increased from 602 to 1,719 (-->286%), i.e. 120 stations p.m.p. The number of patients in regular dialysis treatment rose from 2,127 to 5,335 (-->251%), that means a prevalence of 373 patients p.m.p. In 1989, 67 new patients (p.m.p.) had been accepted for maintenance treatment (incidence), in contrast to 130 new patients p.m.p. in 1994 (-->194%), now under the conditions of unlimited accessibility to dialysis treatment. Questions referring to this point--the incidence of new patients--were only asked in Thüringen (2.5 mio. inhabitants). Alternative treatment modalities became feasible under the new conditions in Eastern Germany. In contrast to 99% hemodialysis patients in December 1989, at the end of 1994 92.8% of the patients were treated by hemodialysis, 2.0% by hemofiltration, and 5.2% by peritoneal dialysis, predominantly CAPD.(ABSTRACT TRUNCATED AT 250 WORDS)
From the petrol extract of the aerial parts of Tribulus cistoides three steroid sapogenins and two N-acyltyramines were isolated, whereas the methanolic extract gave nine steroid saponins, among them the cardioactive cistocardin, saponin-3, saponin-4 and saponin-7. Furthermore, a furostanol diglycoside was isolated besides 5'-(hydroxysulphonyloxy) jasmonic acid, D-(+)-pinitol and sucrose. The structures were established by spectroscopic investigations of the isolated compounds and their hydrolysis products. 5'-(Hydroxysulphonyloxy) jasmonic acid has been prepared by partial synthesis.
Diminished availability of facilities for renal replacement therapy is known to cause spuriously low acceptance and treatment rates. In this context the evolution of renal replacement therapy in the former German Democratic Republic is a useful model to study and to quantify some of the relevant factors. We performed a survey in all dialysis units for adults in East Germany (excluding East Berlin) by questionnaire, achieving a response rate of 97%. From December 1989 to December 1992 the number of dialysis centres increased from 53 to 96 (+81%), reaching 6.7 centres p.m.p. Of these facilities, 45% were hospital units, 29% private units, and 26% dialysis units run by non-profit health care organizations. The number of dialysis stations for regular dialysis treatment increased from 602 to 1276 (+112%), i.e. 89 stations p.m.p. In parallel, the number of chronic dialysis patients increased from 2127 to 3848 (+81%), i.e. 267 patients p.m.p. A more detailed survey was carried out in Thüringen and part of Sachsen, in a region covering 5 million inhabitants. The acceptance rate for chronic dialysis treatment has increased from 49 to 107 patients p.m.p. (+115%). The average age of new patients increased from 49 to 59 years, the proportion of patients aged > or = 65 years increased from 16 to 42% and the proportion of diabetics from 13 to 35%. Introduction of alternative treatment modalities became possible, with 2.3% of the patients receiving haemofiltrations and 3% CAPD. The proportion of HBs-antigen-positive patients decreased from 14.2% to 5%.(ABSTRACT TRUNCATED AT 250 WORDS)