Search Results - (Author, Cooperation:D. Meijer)

2012-05-25

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Action Potentials ; Alkyl and Aryl Transferases/deficiency/genetics/metabolism ; Animals ; Axons/*physiology ; Brain/cytology/metabolism ; Cell Respiration ; Cell Survival ; Demyelinating Diseases/enzymology/genetics/metabolism/pathology ; Electron Transport Complex IV/antagonists & inhibitors/genetics/metabolism ; *Glycolysis ; Lactic Acid/metabolism ; Magnetic Resonance Spectroscopy ; Membrane Proteins/deficiency/genetics/metabolism ; Mice ; Mitochondria/enzymology/genetics/metabolism/pathology ; Mutant Proteins/genetics/metabolism ; Myelin Sheath/*metabolism ; Oligodendroglia/cytology/drug effects/enzymology/*metabolism ; Protons ; Schwann Cells/enzymology/metabolism ; Time Factors

2012-11-09

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Animals ; Binding Sites ; Cell Nucleus/metabolism/pathology ; Female ; Forkhead Transcription Factors/*metabolism ; Gene Expression Regulation/genetics ; Genome/genetics ; Immune Tolerance/genetics/immunology ; Interferon-gamma/deficiency/genetics ; Male ; Mice ; Mice, Inbred C57BL ; Proto-Oncogene Proteins c-akt/metabolism ; Receptors, Antigen, T-Cell/immunology/metabolism ; Signal Transduction ; T-Lymphocytes, Regulatory/*immunology/*metabolism/pathology ; *Transcription, Genetic

0006-291X

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Chemistry and Pharmacology

Physics

Electronic Resource

0167-4781

(Human DNA) ; Cloning ; Cosmid library ; Exon-intron organization ; Neurofilament gene ; Nucleotide sequence

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Chemistry and Pharmacology

Medicine

Physics

Electronic Resource

0922-3371

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Electronic Resource

0303-7207

(Rat) ; Androgen receptorreceptor ; CAT assay ; Promoter

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Medicine

Electronic Resource

0888-7543

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Medicine

Electronic Resource

0039-6028

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Physics

Electronic Resource

1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Soluble heterologous immune complexes (IC) were used to study the mechanism of IC binding to rat liver in vivo. Binding of IC to the various cell types of the liver, endothelial cells, hepatocytes. and Kupffer cells, was only inhibited by aggregated swine immunoglobulins. Binding was not inhibited by the absence of complement components. Intravenous injection of asialoglycoproteins. to block the galactose receptor, could not prevent IC binding. We conclude that Fc receptors play an important role in the binding of soluble heterologous IC to hepatocytes. endothelial cells, and Kupffer cells.

Electronic Resource

1530-0358

Laparoscopy ; Colon ; Surgery

Springer Online Journal Archives 1860-2000

Medicine

Abstract PURPOSE: The dexterity™ pneumo sleeve is designed to provide abdominal access for the surgeon's hand while preserving pneumoperitoneum during laparoscopy. The first experience using the dexterity™ pneumo sleeve in colorectal surgery is reported. METHODS: Four patients with diverticulitis and one with a dolichocolon had manually assisted laparoscopic sigmoid colectomy with the dexterity™ pneumo sleeve. RESULTS: Assistance of the left hand, introduced through the dexterity™ device proved to be extremely helpful in identifying the plane of dissection in one patient with a large diverticular mass and in another with a colovaginal fistula. Mean operative time was 109 minutes, blood loss was 80 ml, and length of incision was 7.5 cm. Flatus reoccurred at the second postoperative day, bowel movement occurred on the third day after surgery, and patients were discharged after 4.8 days. CONCLUSIONS: With the dexterity™ pneumo sleeve, the tactile sensation is regained, which makes laparoscopic-assisted colectomy safer and faster.

Electronic Resource

1435-604X

Transmyocardial revascularization ; Lasers ; Coronary artery disease ; Ischaemia ; Tissue hibernation

Springer Online Journal Archives 1860-2000

Medicine

Physics

Technology

Abstract Transmyocardial revascularization (TMR) is a puncture technique proposed as a solution for patients with coronary artery disease who cannot be efficiently treated with the standard revascularization procedures such as bypass surgery or percutaneous transluminal coronary angioplasty (PTCA). The studies presented in this review have investigated the use of lasers to revascularize ischaemic myocardium. Needle puncture methods are also briefly described. The results from experimental studies are not conclusive but the encouraging clinical reports raise further questions about the mechanism of angina relief.

Electronic Resource

1433-4909

Key wordsHalomonas magadii sp. nov. ; Alkaliphile ; Soda lake ; 16S rDNA ; Phylogeny ; Halomonad taxonomy

Springer Online Journal Archives 1860-2000

Biology

Abstract A number of novel alkaliphilic organotrophic bacteria have been isolated from several saline and alkaline East African soda lakes. The new isolates grow at pH values between 7.0 and 11.0, with pH optima for growth between 9.0 and 10.0. Growth occurs at total salts concentration between 0% and 20% (w/v) with optimum at 0%–7% (w/v). Phylogenetic analyses based on 16S rDNA sequence comparison indicate that these isolates are related (〉96% similarity) to members of the Halomonadaceae within the γ-3 subdivision of the Proteobacteria. These analyses indicate that existing species within the Halomonadaceae fell within three main groups, one group comprising the type species of Halomonas, Halomonas elongata, and a number of other known species including one soda lake isolate. A second group constituting most of the remaining known species of Halomonas and related Chromohalobacter spp. includes 3 soda lake isolates with high DNA–DNA homologies. The third group included Halomonas halodenitrificans, Halomonas desiderata, Halomonas cupida, and 13 soda lake isolates. Phenotypic comparisons indicated that the majority of soda lake strains shared similar morphological, phenotypic, and chemotaxonomic properties to known strains of Halomonas but grew under alkaline conditions. The 3 soda lake isolates with high DNA–DNA homologies were, however, significantly different in antibiotic sensitivity pattern and in the utilization of several substrates, were unable to reduce nitrite, and showed low DNA–DNA homologies with known halomonads in the same group. We propose that these isolates comprise a new species of the genus Halomonas that we name Halomonas magadii sp. nov. The type strain is strain 21 MI (NCIMB 13595).

Electronic Resource

1432-1912

Deptropine Methiodide ; N-Methyltropine ; Perfused Liver

Springer Online Journal Archives 1860-2000

Medicine

Summary The metabolism of 3α-[(10,11-dihydro-5H-dibenzo-[a,d]cyclohepten-5-yl)oxy]-8-methyltropanium iodide (deptropine methiodide; N-methyldeptropine), a potential agent for the treatment of peptic ulcers and gastrointestinal spasms, was studied by passing the N-14CH3-labelled compound through the isolated perfused rat liver. The substance was rapidly taken up by the liver. This process followed first-order kinetics with a half-life of 5 min. It was calculated that 94% of the drug was removed by the liver during one passage. About 70% of the initial radioactivity was excreted in the bile during a perfusion period of 2 h. This elimination process exhibited first-order kinetics with a half-life of about 25 min. N-Methyldeptropine was found to be broken down in the liver into N-methyltropine, and a non radioactive fragment. N-methyltropine and N-methyldeptropine were eliminated in the bile. The former also diffused back into the perfusion fluid. In addition, the bile contained an uncharacterised radioactive product related to N-methyltropine, possibly a complex of N-methyltropine with bile components. Both the rapid uptake of N-methyldeptropine in the liver and the biotransformation into products with a much lower pharmacological and toxicological potency, should lessen the likelihood of side effects outside the gastrointestinal tract after oral dosage.

Electronic Resource

1432-1912

Biliary Excretion ; Choleresis ; ICG ; Hepatic Uptake Mechanisms ; Bile Acids ; Dehydrocholic Acid

Springer Online Journal Archives 1860-2000

Medicine

Summary The pharmacokinetics of indocyanine green (ICG; 3.9 μmoles/kg and 12.9 μmoles/kg) were investigated in rats given infusion of either saline, taurocholate (106 μmoles/h) or dehydrocholate (106 or 268 μmoles/h). During the infusion of saline and taurocholate the plasma concentration of ICG decreased in a mono-exponential manner. However, with dehydrocholate the clearance of ICG from plasma showed two phases with different half lives. The half life of the rapid component (2.2 min) was about the same as the one found in the control experiments. After injection of 12.9 μmoles/kg ICG the biliary excretion of the dye increased by 138% during taurocholate administration, while an equimolar dehydrocholate infusion resulted in a mean increament of 55%. Under these circumstances the bile flow was stimulated by 195% and 297% resp. With the lower dose of ICG (3.9 μmoles/kg) however, there was no stimulation of the biliary ICG excretion with taurocholate. At this dose level an infusion of dehydrocholate (106 μmol/h) enchanced the biliary output of ICG by approximately 54%, while administration of 268 μmol/h resulted in a slight but significant decrease of 31%. These observations can be explained by assuming interaction of the bile acids with the hepatic transport of ICG at different sites. The appearance of the second component of the plasma curve during dehydrocholate infusion is possibly related to a diminished hepatic storage capacity for ICG and is not due to an effect on the primary hepatic uptake or biliary output of the dye.

Electronic Resource

1434-0879

Collagen ; PDSC ; Continent ileostomy ; Continent urostomy

Springer Online Journal Archives 1860-2000

Medicine

Summary Complications of the nipple valve system used for continent urostomy and ileostomy basically consist of incomplete (or complete lack of) adhesion of the invaginated serosal surfaces of the valve. A novel concept in fixation of the valve by means of the intussusception of a newly developed biomaterial (processed dermal sheep collagen; PDSC) was tested. The implanted PDSC is characterized by induction of fibroblast invasion and formation of new collagen fibers, initial high tensile strength, bio-inertion and (slow) biodegradation. It was implanted between the serosal surfaces of the invagination in 14 dogs without the application of the commonly used staples and synthetic mesh. Good permanent fixation was obtained in all cases after the PDSC had been sutured in place. As the observation time advanced up to 2 years, an increased amount of newly formed collagen was seen anchoring the serosal surfaces firmly together via the implanted PDSC with apparent slow degradation. In none of the test animals did complications accur. The first clinical trial was successful.

Electronic Resource

1432-1912

Biliary excretion ; Cardiac glycosides ; Choleresis ; Bile acids ; Bile micelles

Springer Online Journal Archives 1860-2000

Medicine

Summary To investigate binding of drugs to biliary micelles as a possible factor in the hepatic transport process, interaction of two uncharged compounds, 3H-ouabain and 3H-K-strophanthoside with biliary micelles was studied by ultracentrifugation of bile. The various bile acids normally present in rat bile were predominantly associated with cholesterol containing micelles, but not to the same extent. The tendency of the bile salts to be associated with mixed micelles was the greatest for conjugated chenodeoxycholate, somewhat lower for conjugated deoxycholate and the least for conjugated cholate. The sedimentation patterns of the water-soluble cardiac glycosides, added in vitro, indicated binding to mixed biliary micelles as well as non-cholesterol containing micelles. Also mannitol, a drug used to estimate canalicular bile flow, was found to be associated with both categories of biliary micelles. In spite of the binding of cardiac glycosides to the micelles, administration of taurocholate, which promotes formation of biliary micelles, did not stimulate biliary output of both glycosides. Also administration of the choleretics dehydrocholate and ethacrynic acid failed to enhance biliary output of the glycosides. These results indicate, that binding of drugs to biliary micelles diminishes the free concentration of drugs in bile and confirms earlier studies with organic anions that binding to biliary micelles is not a pertinent factor in the rate of biliary excretion.

Electronic Resource

1432-1912

Biliary excretion ; Bile acids ; Choleresis ; Quaternary ammonium compounds ; d-Tubocurarine ; Acetyl procainamide ethobromide

Springer Online Journal Archives 1860-2000

Medicine

Summary The influence of the bile salts taurocholate and dehydrocholate on the hepatic transport of two quaternary ammonium compounds,d-tubocurarine (dTc) andN 4-acetylprocainamide ethobromide (APAEB) was investigated in rats. The biliary excretion of APAEB and dTc in vivo was not enhanced by 106 μmoles/h of taurocholate or dehydrocholate. Infusion of 268 μmoles/h dehydrocholate caused an inhibition of the plasma disappearance and hepatic transport of dTc. This inhibition, which presumably occurred at the hepatic uptake level, was also observed in isolated perfused rat liver experiments. In animals with an intact renal function, the high dose of dehydrocholate caused a decreased biliary excretion and an increased renal excretion of dTc. The observed concentration gradients, plasma/liver cytosol and bile/liver cytosol 20 min after injection of both drugs were 1.6 and 23 for APAEB and 2.2 and 190 for dTc. These concentration ratios were based on free drug concentrations; corrections were made for plasma protein binding, intracellular binding and biliary micelle binding. No substantial binding of both compounds to ligandin and Z proteins was found. From the amount in the liver 20 min after injection of both drugs 70% of APAEB and 90% of dTc was bound to cellular particles. The rate limiting step in hepatic transport of APAEB from plasma into bile was concluded to be the hepatic uptake, which may explain the lack of effect of bile salt induced choleresis on its biliary excretion.

Electronic Resource

1432-1041

indocyanine green ; pharmacokinetics ; biliary excretion ; liver function test

Springer Online Journal Archives 1860-2000

Chemistry and Pharmacology

Medicine

Summary The pharmacokinetics of Indocyanine Green (ICG) has been studied in 15 patients given 0.5, 1.0 and 2.0 mg · kg−1. The plasma disappearance and biliary excretion rate were measured in patients with tightly fitting catheters under slight negative pressure in order to achieve complete collection of bile. Recovery of unchanged ICG in bile over 18 h after the i.v. injection was 80% of the dose in all three dose groups. Plasma disappearance in all 3 groups was biphasic, showing an initial phase with a t1/2 of 3–4 min and a secondary phase with a dose-dependent apparent t1/2 of 67.6, 72.5 and 88.7 min, respectively. After 0.5 and 1.0 mg · kg−1 the biliary excretion rate curves showed an ascending phase with a mean t1/2 of 5 min and a descending phase with a mean t1/2 of 72 min. It was inferred that the secondary component of the plasma-decay mainly reflected the biliary excretion rate. After 2.0 mg · kg−1 in some patients the biliary excretion curve showed features of saturation; the t1/2 of the descending phase ranged from 73 to 440 min, and the time of maximal excretion was increased from 1.3 to 2.7 h after injection, whilst the mean maximal excretion rate was in the same range as the excretion rate after the 1.0 mg · kg−1 dose. The non-linear pharmacokinetics was only moderately reflected in the measured plasma disappearance patterns. Two compartment analysis of the plasma levels indicated a clearance of 230–260 ml · min−1, whereas the clearance conventionally calculated from the initial t1/2 was 475 ml · min−1. The volume of the central compartment in 70 kg patients was 2.31, which is about the plasma volume. The fictive volume of distribution in the liver (V2) was 70–90 l, indicating marked hepatic storage of ICG. This was probably due to the very low liver-to-plasma transport rate (k21) of 0.006–0.10 min−1. Thus, the biliary excretion of ICG can be quantified by 2-compartment pharmacokinetic analysis of plasma disappearance curves, including a secondary phase. The latter, slow component was apparent at very low plasma levels due to the marked hepatic storage, and it was also influenced by retention of small amounts of impurities or degradation products. Improved detectability of this phase cannot simply be obtained by increasing the dose, since at doses exceeding 1.0 mg · kg−1 non-linear elimination may complicate the pharmacokinetic analysis.

Electronic Resource

1432-1041

dibromosulfophthalein ; pharmacokinetics ; plasma levels ; urinary excretion ; biliary excretion ; biliary fistula ; enterohepatic circulation ; hepatic transport test

Springer Online Journal Archives 1860-2000

Chemistry and Pharmacology

Medicine

Summary The pharmacokinetics of dibromosulfophthalein (DBSP), the 3,6-dibromo analogue of BSP, was studied in 7 patients with a biliary fistula, 52 h after cholecystectomy, and in 6 gynaecological patients with an indwelling urethral catheter, following extirpation of the uterus i.e. with an intact enterohepatic circulation. Plasma protein binding determined by ultrafiltration was 98–99% up to a concentration of 700 µg/ml. After an intravenous bolus injection of DBSP 5 mg/kg, a biexponential plasma decay was found in both groups, with a rapid initial t1/2 of 2–6 min and a slow secondary phase of 33–109 min (mean 66 min) in the cholecystectomy patients, and 10–30 min (mean 19 min) in the gynaecological patients. The biliary excretion rate varied considerably between the patients and was highly correlated with bile flow. Biliary output amounted to a maximum of 86% of the dose in 24 h. The excretion rate curves showed ascending and descending phases, the mean terminal t1/2 being 65 min. Urinary excretion was 3–11% of the dose in 8 h in the gynaecological patients (mean 6%) and 6–31% in the cholecystectomy group (mean 16%). Renal clearance of unbound DBSP was about ten-times greater than the glomerular filtration rate, which indicates tubular secretion. A two compartment model with elimination from the peripheral and central compartments was selected because of these data. Analysis of the plasma-disappearance curves indicated an initial plasma clearance of 500–600 ml/min, which suggests that hepatic uptake will be very dependent on flow. Steady state (biliary) clearance was about 400 ml/min in the gynaecological group and approximately half that in the cholecystectomy patients; V1 tended to be higher and V2 to be lower in the latter group. It is concluded that biliary excretion rate of DBSP in patients with a biliary fistula is probably depressed by the postoperative bile drainage and the lack of enterohepatic cycling of bile salts.

Electronic Resource

1432-1041

Bezitramide ; oral absorption profile ; pharmacokinetics ; male volunteers ; experimental pain ; biliary excretion in rats

Springer Online Journal Archives 1860-2000

Chemistry and Pharmacology

Medicine

Summary The oral absorption of bezitramide 5 mg was studied in 7 human volunteers, using a specific radioimmuno-assay which measured both bezitramide and its active metabolite R-4618. A lag time of 0.5–1.0 h and a Cmax of 5.4 ng/ml plasma were found, the latter occurring 2.5–3.5 h after administration. The apparent elimination half-life varied from 11 to 24 h. Less than 0.3% of the dose was excreted unchanged in the urine. High concentrations in the faeces of some individuals indicate incomplete absorption and/or biliary secretion. The analgesic effect, using a standardized superficial electrical stimulation method, reached its maximum between 2.5 and 3.5 h after dosing, in accordance with the absorption phase. The duration of the effect was highly variable. Experiments in rats (n=6,3H-bezitramide 2.5 µg), demonstrated extensive biliary excretion (up to 70% of total radioactivity) and less than 3% of the label was removed by urinary excretion.

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