Factors affecting in vitro protein binding of etoposide in humans.

Clinical studies have demonstrated that the plasma protein binding of etoposide, a widely used anticancer drug, is extensive (approximately 94%), highly variable among patients (10-fold range), and significantly related to serum albumin and total bilirubin concentration. The present study was designed to more thoroughly evaluate factors likely to affect etoposide protein binding under controlled in vitro conditions where single variables could be changed. Protein binding was determined using an equilibrium dialysis method with tritiated etoposide.

Regulation of hepatic secretion of very low density lipoprotein by dietary cholesterol.

Male rats were fed a cholesterol-free diet or the same diet supplemented with either 0.05, 0.1, 0.

DNA sequence characterization of the G gene region of bacteriophage Mu.

The nucleotide sequence of a 1.2 kb region of bacteriophage Mu DNA was determined. This region contains the 3' end of the F gene, the complete G gene, and the 5' end of the I gene, all late genes involved in Mu virion morphogenesis.

Fatty acid composition of hepatic triglycerides in Reye's syndrome: implications for hepatic desaturase abnormalities.

Serum NEFA profiles in Reye's syndrome are reportedly unique with a disproportionate percent made up of polyunsaturated fatty acids some of which are not ordinarily found in the serum. This pattern is also reflected in the serum triglyceride composition as well. As the liver is probably the sole source of the serum triglyceride in Rye's syndrome because patients are vomiting or in coma, the fatty acid acid composition of the liver triglyceride was examined for insight regarding the lipid abnormalities in this disease.

Comparison of subjective ratings of function with observed functional ability of frail older persons.

Background: Important clinical decisions often hinge on patients' functional status. Previous studies have shown disagreement among sources of ratings of patients' functional status. This study compared patient self-ratings, family member ratings, and physician ratings of patient function to performance-based functional testing criteria.

Mechanism of neurotransmitter release elicited by the preferential alpha 1-adrenergic receptor agonist phenylephrine in superfused superior cervical ganglion cells in culture.

Phenylephrine increased [3H]norepinephrine efflux and accumulation of cyclic AMP in cultured rat superior cervical ganglion cells superfused with Tyrode's solution. The purpose of this study was to determine the mechanism and relationship between these two events. Electrical stimulation (1-2 Hz), potassium chloride (50 mM), and the preferential alpha 1-adrenergic receptor agonist phenylephrine (1-100 microM) increased fractional tritium efflux, whereas methoxamine, cirazoline, and amidephrine were relatively ineffective.

Mass spectrometric quantification of endogenous beta-endorphin.

Fast atom bombardment (FAB) mass spectrometry and multiple reaction monitoring (MRM) in the B/E linked-field scan mode were used to quantify endogenous beta-endorphin (BE) in individual human pituitary extracts. The experimental protocol includes the addition of a stable isotope-labeled internal standard ((2H4-Ile22)BE1-31, human) to the tissue homogenate before extraction, purification of the native BE by a combination of Sep-Pak chromatography and gradient high-performance liquid chromatography (HPLC), trypsin digestion to cleave BE into smaller peptides, and separation of the tryptic fragment BE20-24 (NAIIK) by isocratic reversed-phase HPLC. Mass spectrometric quantification is based upon recording either (a) the [M + H]+ ions of NAIIK and its deuterated analog ((2H4)NAIIK), or (b) the transitions ([NAIIK + H](+)----[NAI]+) and [((2H4)NAIIK + H](+)----[(2H4)NAI]+) using the B/E linked-field scan.

Cervicothoracic arterial injuries: recommendations for diagnosis and management.

Management of arterial injuries at the thoracic outlet and neck presents a major challenge to the trauma surgeon: hemorrhagic shock, neurologic deficit, and limb loss are the serious sequelae. Over a 13-year period, 118 patients with injuries to the innominate, carotid, subclavian, and axillary arteries were evaluated. Most injuries were penetrating (78%).

Chiral resolution of alpha,alpha'-bis[3-(N,N-diethylcarbamoyl)piperidino]-p-xylene, a novel antiplatelet compound.

alpha,alpha'-Bis[3-(N,N-diethylcarbamoyl)piperidino]-p-xylene dihydrobromide, a novel antiplatelet agent, was resolved into three isomers A, B, and C, on a chiral alpha 1-acid glycoprotein analytical column using a mobile phase of 0.025 M phosphate buffer containing 0.025 M tetrabutylammonium hydrogen sulfate, at a pH of 6.

Quality of life in children and adolescents with cancer.

Quality of life for children and adolescents who have cancer is a personal, subjective experience that is influenced by the individual's internal, immediate, and institutional environments. Quality of life is most accurately assessed on an individual basis with each child or adolescent serving as his/her own standard.

The patterns of neurotransmitter and neuropeptide co-occurrence among striatal projection neurons: conclusions based on recent findings.

The neurotransmitter organization of striatal projection neurons appears to be less complex than once thought. Only 4 major evolutionarily conserved populations appear to be present. The neurons of two of these populations contain SP, DYN and GABA, with one of these two populations consisting of striatonigral projection neurons and the other of striatopallidal projection neurons.

Cholesterol is required for the secretion of the very-low-density lipoprotein: in vivo studies.

Rats were fed for 1 week with a standard chow diet, a diet supplemented with lovastatin (0.1%), or a diet supplemented with both lovastatin and cholesterol (0.1/0.

Initial experience with a universal-length copolymer ureteral stent.

A universal-length ureteral stent made of a biocompatible copolymer was designed specifically for easy antegrade internal placement. The double-looped distal end of the stent eliminates the need to measure the distance from the ureteropelvic to ureterovesical junction. If additional length is required, a portion of the distal loop is incorporated into the stent shaft.

Angiotensin II binding sites in aortic endothelium of domestic fowl.

In domestic fowl, angiotensin II (ANG II) produces a unique vasodepressor response in vivo and endothelium-dependent relaxation of aortic rings in vitro that appear to be a direct effect on vascular smooth muscle mediated through vascular angiotensin receptors. To explore the possible role of the endothelium in ANG II-induced vasodilation, ANG II binding to aortic membrane fractions and intact endothelium and prostaglandin (PG) production were examined in fowl aortas. 125I-[Ile5]ANG II binding by endothelium-intact aortic membrane fractions was consistently higher than binding by identically prepared endothelium-deleted membrane fractions at virtually all concentrations of ligand (10 pM-0.

Activation of the bacteriophage Mu lys promoter by Mu C protein requires the sigma 70 subunit of Escherichia coli RNA polymerase.

Bacteriophage Mu C protein, a product of the middle operon, is required for activation of the four Mu late promoters. To address its mechanism of action, we overproduced the approximately 16.5-kilodalton C protein from a plasmid containing the C gene under the control of a phage T7 promoter and ribosome-binding site.

Somnogenic activity of immune response modifiers.

Sleepiness is a presenting symptom in nearly all infectious diseases. James Krueger describes how microbial products, such as muramyl peptides, lipid A and double-stranded RNA, as well as endogenous products elicited by these substances, such as interleukin 1, modulate sleep. The altered sleep during infection seems to result from an exaggerated activation of physiological sleep mechanisms, since normal sleep is controlled by a wide range of substances including many of these immune response modifiers.

Topographic organization of baboon primary motor cortex: face, hand, forelimb, and shoulder representation.

(1) The fine details of the motor organization of the forelimb, face, and tongue representation of the baboon (Papio h. anubis) primary motor cortex were studied in four adult animals, using intracortical microstimulation (ICMS). (2) A total of 293 electrode penetrations were made.

Characterization of the C operon transcript of bacteriophage Mu.

Mu transcription occurs in three phases: early, middle, and late. Middle transcription occurs in the region of the C gene, which encodes the transactivator for late transcription. A middle promoter, Pm, was previously localized between 0.

Lactate, oxygen uptake, and cycling performance in triathletes.

To assess the relationship of exercise test variables to each other and to bike race times in an ultra-distance triathlon, we studied 24 participants (14 men, 10 women) in the 1985 Hawaii Ironman Triathlon, using a graded, maximal cycle ergometer test with gas exchange and blood lactate (LA) measurements at each work load. Exercise test variables were oxygen uptake (VO2) and heart rate (HR) at the lactate and ventilatory thresholds. Lactate threshold (LT-1) was defined as the exercise intensity that elicited a 1 mM increase in blood lactate concentration above the value measured during the first work load for each subject.

Characterization of phosphorylated amino acids by fast-atom bombardment mass spectrometry.

Positive- and negative-ion fast-atom bombardment (FAB) mass spectrometry and linked-field scan techniques at constant B/E are used to characterize phosphorylated serine, threonine, and tyrosine amino acids. Abundant molecular ions are formed for all three amino acids in both modes of ionization. The dominant fragmentation is cleavage of the phosphate ester bond with charge retention in positive-ion FAB by the amino acid backbone and in the negative-ion mode by the phosphate group.

Cholesterol is required for secretion of very-low-density lipoprotein by rat liver.

To study potential effects of hepatic cholesterol concentration on secretion of very-low-density lipoprotein (VLDL) by the liver, male rats were fed on unsupplemented chow, chow with lovastatin (0.1%), or chow with lovastatin (0.1%) and cholesterol (0.

Stimulation of hepatic cholesterol biosynthesis by fatty acids. Effects of oleate on cytoplasmic acetoacetyl-CoA thiolase, acetoacetyl-CoA synthetase and hydroxymethylglutaryl-CoA synthase.

The effects of oleic acid on the activities of cytosolic HMG-CoA (3-hydroxy-3-methylglutaryl-CoA) synthase, AcAc-CoA (acetoacetyl-CoA) thiolase and AcAc-CoA synthetase, as well as microsomal HMG-CoA reductase, all enzymes in the pathway of cholesterol biosynthesis, were studied in the isolated perfused rat liver. Oleic acid bound to bovine serum albumin, or albumin alone, was infused for 4 h at a rate sufficient to sustain an average concentration of 0.61 +/- 0.

Distribution of mu, delta, and kappa opiate receptor types in the forebrain and midbrain of pigeons.

Ligands that are highly specific for the mu, delta, and kappa opiate receptor binding sites in mammalian brains have been identified and used to map the distribution of these receptor types in the brains of various mammalian species. In the present study, the selectivity and binding characteristics in the pigeon brain of three such ligands were examined by in vitro receptor binding techniques and found to be similar to those reported in previous studies on mammalian species. These ligands were then used in conjunction with autoradiographic receptor binding techniques to study the distribution of mu, delta, and kappa opiate receptor binding sites in the forebrain and midbrain of pigeons.

Role of brain acetylcholine in vasopressin release during osmotic stimulation and hemorrhage.

There is considerable evidence to suggest that there is a cholinergic link in the neural control of vasopressin release, but the precise role for this link has not been adequately demonstrated in the intact animal. We have, therefore, examined in conscious unrestrained rats the effects of central cholinergic blockade on the stimulation of vasopressin release by increased plasma osmotality (iv infusion of 2.5 M NaCl at 0.