Preliminary Genetic Studies of the Phenotype of Betaine Deficiency in Zea mays L.

Glycinebetaine-deficient inbreds of Zea mays do not exhibit a general deficiency of nitrogenous solutes; the total free amino acid levels of betaine-deficient lines are not significantly less than those of inbreds which exhibit >100-fold higher betaine levels. Betaine-deficient inbreds are characterized by extremely low betaine: total free amino acid ratios (<0.0015).

Structure and location of amiodarone in a membrane bilayer as determined by molecular mechanics and quantitative x-ray diffraction.

Amiodarone is a drug used in the treatment of cardiac arrhythmias and is believed to have a persistent interaction with cellular membranes. This study sought to examine the structure and location of amiodarone in a membrane bilayer. Amiodarone has a high membrane partition coefficient on the order of 10(6).

Influence of epinephrine on alcohol dehydrogenase activity in rat hepatocyte culture.

The effects of epinephrine on alcohol dehydrogenase activity and on rates of ethanol elimination were determined in rat hepatocyte culture. Continuous exposure of the hepatocytes to epinephrine (10 microM) in combination with dexamethasone (0.1 microM) enhanced alcohol dehydrogenase activity on days 4-7 of culture, whereas neither hormone alone had an effect.

Amino Acid Metabolism of Lemna minor L. : III. Responses to Aminooxyacetate.

Aminooxyacetate, a known inhibitor of transaminase reactions and glycine decarboxylase, promotes rapid depletion of the free pools of serine and aspartate in nitrate grown Lemna minor L. This compound markedly inhibits the methionine sulfoximine-induced accumulation of free ammonium ions and greatly restricts the methionine sulfoximine-induced depletion of amino acids such as glutamate, alanine, and asparagine. These results suggest that glutamate, alanine, and asparagine are normally catabolized to ammonia by transaminase-dependent pathways rather than via dehydrogenase or amidohydrolase reactions.

Changes in erythrocyte enzyme activities during erythrocyte aging in alcoholism.

Aldehyde dehydrogenase, glucose-6-phosphate dehydrogenase, and pyruvate kinase activities were determined in erythrocytes of various ages, separated by Percoll gradient centrifugation, in 13 alcoholic patients and eight control subjects. The total erythrocyte activities of all three enzymes were not affected by alcoholism, however, the youngest cells of alcoholics had a decreased aldehyde dehydrogenase activity, while both glucose-6-phosphate dehydrogenase and pyruvate kinase activities were increased. The depression of aldehyde dehydrogenase activity not only persisted, but became more marked after 2 weeks of abstinence, while the enhanced activities of the two other enzymes returned to normal.

Teaching nurses therapeutic conversation: a pilot study.

A 2-day video-based workshop developed for teaching psychiatrists was used to instruct learner psychiatric nurses in the conversational model of psychotherapy. A small evaluation was carried out to assess the effects of the teaching on the performance of these nurses in interviewing other learner nurses who role-played people with common emotional difficulties. A randomized groups design was used comparing the interview behaviour of experimental and control groups before and after the workshops, and at 3 months follow-up.

Zinc-finger motifs expressed in E. coli and folded in vitro direct specific binding to DNA.

The short sequence motif named 'zinc finger', first recognized repeated in tandem in the Xenopus transcription factor IIIA (TFIIIA), is also found in the yeast transcriptional activator SWI5 (ref. 3) and many other regulator proteins. Embedded in the 709-amino-acid polypeptide chain of SWI5 are three tandemly repeated zinc-finger motifs.

The impact of DRGs on the cost and quality of health care in the United States.

The prospective Payment System (PPS) represents a fundamental change in the way the United States government reimburses hospitals for medical services covered under Medicare, a federal health care insurance program for the elderly and disabled. PPS replaced the retrospective cost-based system of payment for Medicare services with a prospective payment system. Under PPS, a predetermined specific rate for each discharge dictates payment according to the diagnosis related group (DRG) in which the discharge is classified.

Characterization of human erythrocyte aldehyde dehydrogenase.

Human erythrocyte aldehyde dehydrogenase was purified to homogeneity. The enzyme exhibited a single band of activity on starch gel electrophoresis and on isoelectric focusing. It was a tetramer with an estimated molecular weight of 230,000 daltons and an isoelectric point of 5.

Abscisic Acid Stimulated Osmotic Adjustment and Its Involvement in Adaptation of Tobacco Cells to NaCl.

Osmotic adjustment of cultured tobacco (Nicotiana tabacum L. var Wisconsin 38) cells was stimulated by 10 micromolar (+/-) abscisic acid (ABA) during adaptation to water deficit imposed by various solutes including NaCl, KCl, K(2)SO(4), Na(2)SO(4), sucrose, mannitol, or glucose. The maximum difference in cell osmotic potential (Psipi) caused by ABA treatment during adaptation to 171 millimolar NaCl was about 6 to 7 bar.

Solute Accumulation in Tobacco Cells Adapted to NaCl.

Cells of Nicotiana tabacum L. var Wisconsin 38 adapted to NaCl (up to 428 millimolar) which have undergone extensive osmotic adjustment accumulated Na(+) and Cl(-) as principal solutes for this adjustment. Although the intracellular concentrations of Na(+) and Cl(-) correlated well with the level of adaptation, these ions apparently did not contribute to the osmotic adjustment which occurred during a culture growth cycle, because the concentrations of Na(+) and Cl(-) did not increase during the period of most active osmotic adjustment.

Determination of Betaines by Fast Atom Bombardment Mass Spectrometry : Identification of Glycine Betaine Deficient Genotypes of Zea mays.

A rapid, sensitive, and selective method for the determination of betaines is described and discussed. The method entails derivatizing the quaternary ammonium compounds to increase their sensitivity to detection by fast atom bombardment mass spectrometry. Sensitivity of detection increases markedly as the length of the carbon chain of the alcohol used to esterify the betaine carboxylic acid group is increased (C4 > C3 > C2 > C1 > C0).

Amino Acid Metabolism of Lemna minor L. : II. Responses to Chlorsulfuron.

Chlorsulfuron, an inhibitor of acetolactate synthase (EC 4.1.3.

Drop-size measurement techniques for sprays: comparison of Malvern laser-diffraction and Aerometrics phase/Doppler.

The purpose of this paper is to compare the drop sizing results of an Aerometrics phase/Doppler particle analyzer with those of a Malvern laser-diffraction instrument. Measurements were performed on a small pressure-swirl atomizer. Since the laser-diffraction instrument measures a line-of-sight average through different regions of the spray while the phase/Doppler instrument characterizes the spray in a small volume, a conversion procedure was necessary prior to comparison.

Water metabolism in free-ranging pine voles (Microtus pinetorum).

Rates of body water turnover in free-ranging pine voles exceeded those reported for a large number of similarly sized mammals. Concentrations of urine obtained from free-ranging pine voles were significantly lower than values published for other free-ranging mammals and also for laboratory-maintained members of this species. Rates of body water turnover in this species were not correlated with seasonal changes in soil temperatures.

Mapping of the sites of protection on a 5 S RNA gene by the Xenopus transcription factor IIIA. A model for the interaction.

The contact points of transcription factor IIIA with the internal control region of the 5 S RNA gene of Xenopus have been investigated by probing the accessibility of the DNA in the protein-DNA complex to dimethylsulphate and to micrococcal nuclease. The results of quantitative measurements, combined with those from earlier DNase I and DNase II protection studies, are consistent with a series of multiple contacts about five base-pairs apart, or half a double-helical turn, along the whole length of the internal control region. The nine patches of contact we have mapped could correspond to nine DNA-binding fingers in the protein.

Metabolic changes associated with adaptation of plant cells to water stress.

Suspension cultured cells of tomato (Lycopersicon esculentum Mill. cv VFNT Cherry) adapted to water stress induced with polyethylene glycol 6000 (PEG), exhibit marked alterations in free amino acid pools (Handa et al. 1983 Plant Physiol 73: 834-843).

Amino Acid Metabolism of Lemna minor L. : I. Responses to Methionine Sulfoximine.

When Lemna minor L. is supplied with the potent inhibitor of glutamine synthetase, methionine sulfoximine, rapid changes in free amino acid levels occur. Glutamine, glutamate, asparagine, aspartate, alanine, and serine levels decline concomitantly with ammonia accumulation.

Intake of a liquid diet after 2-deoxy-D-glucose injections in rats.

The effects of a liquid diet after 2-deoxy-D-glucose (2DG) were examined following water deprivation, after food deprivation, and at longer post-injection intervals when animals reportedly are hypophagic as a function of drug treatment. Water deprived rats were unable to increase their post-drug feeding when ingesting the liquid diet; and in food deprived subjects, intake patterns of liquid diet and of lab chow pellets were essentially identical after 2DG. The tendency of a 750 mg/kg dosage to produce a longer-term hypophagic reaction was more evident in animals given pellets instead of the liquid diet.

Effect of growth hormone on alcohol dehydrogenase activity in hepatocyte culture.

The effect of growth hormone on the activity of alcohol dehydrogenase was determined in hepatocyte culture from normal and hypophysectomized male rats. Alcohol dehydrogenase activity was highest in hepatocytes harvested from hypophysectomized rats. The enzyme activity remained stable in hepatocytes harvested from normal rats during 2 to 6 days of culture but declined steadily in hepatocytes cultured from hypophysectomized rats.

Effect of glucagon on alcohol dehydrogenase activity in rat hepatocyte culture.

The effect of glucagon on the activity of alcohol dehydrogenase in rat hepatocyte culture was determined. Glucagon concentrations of 0.1 nM enhanced, whereas concentrations greater than 1 nM decreased, alcohol dehydrogenase.

An underlying repeat in some transcriptional control sequences corresponding to half a double helical turn of DNA.

Transcription factor IIIA, which binds to the internal control region of the Xenopus 5S RNA gene has a novel structure consisting of nine tandemly repeated structural units. It was proposed by us that each unit interacts with about 5 bp of DNA. We show here that there is a periodicity on this scale in the DNA sequence and, by fine scale probing with nucleases, a corresponding structural repeat.