Duodenal phytohaemagglutinin (red kidney bean lectin) stimulates gallbladder contraction in humans.

Aim: Lectins, carbohydrate-specific proteins without enzymatic activity on the ligand, are daily ingested plant proteins which survive the passage through the gastrointestinal tract in a biologically active form. Their binding to glycan determinants of natural glycoconjugates can trigger biological effects. The lectin phytohaemagglutinin (PHA) is abundantly present in red kidney beans and induces cholecystokinin (CCK) release in rats.

Role of free fatty acids in regulating gastric emptying and gallbladder contraction.

The limited effectiveness of orlistat, an inhibitor of gastrointestinal lipases, in inhibiting fat digestion is not completely understood. Therefore we studied the effect of orally and duodenally administered orlistat on gastric emptying, cholecystokinin (CCK) secretion, and gallbladder contraction. In healthy males, gastric emptying of solids and fat were quantified scintigraphically, gallbladder contraction by ultrasound and CCK release by radioimmunoassay.

Effects of a preload on reduction of food intake by GLP-1 in healthy subjects.

Background/aims: Glucagon-like peptide-1 (GLP-1) inhibits food intake in animals and humans. Whether GLP-1 interacts with other satiety signals to modulate food intake is unknown. We investigated therefore in healthy volunteers the potential interactions of GLP-1 with signals from the stomach in regulating food intake.

Interaction between GLP-1 and CCK-33 in inhibiting food intake and appetite in men.

Glucagon-like peptide-1 (GLP-1) and CCK-33 were intravenously infused alone or in combination into normal weight men for 60 min before they were served a lunch of ham sandwiches, chocolate mousse, and orange juice. Infusion of GLP-1 (dose: 0.9 pmol x kg(-1) x min(-1)) or CCK-33 (dose: 0.

Tegaserod, a 5-HT4 receptor partial agonist, accelerates gastric emptying and gastrointestinal transit in healthy male subjects.

Background: Serotonin and its type-4 (5-hydroxytryptamine4) receptor play a major role in the physiology of the gastrointestinal tract. The effect of intravenous and/or oral tegaserod, a 5-hydroxytryptamine4 receptor partial agonist, on gastric emptying, small bowel transit and colonic transit has not been studied in detail in humans.

Aim: To assess the pharmacodynamic effects of repeated oral and intravenous administration of tegaserod on gastric emptying and small intestine and colonic transit.

The effect of cholecystokinin in controlling appetite and food intake in humans.

The present review of the satiating effect of cholecystokinin in humans has revealed that cholecystokinin is a physiological satiety factor in humans. The results demonstrate the efficacy of the satiating actions of exogenous and endogenous CCK in humans. The therapeutic potential of CCK analogues cannot be estimated until further studies are performed that demonstrate the efficacy of CCK analogues for decreasing body weight, and the safety of CCK when administered repetitively for prolonged periods.

Loxiglumide, a CCK-A receptor antagonist, stimulates calorie intake and hunger feelings in humans.

Exogenous cholecystokinin (CCK) induces early satiety when infused into humans. Whether alimentary CCK (CCK-A) receptor blockade stimulates food intake in humans is, however, uncertain. The aim of the present investigation was, therefore, to establish the effect of CCK-A receptor blockade on satiety and eating behavior in healthy volunteers.

The role of long chain fatty acids in regulating food intake and cholecystokinin release in humans.

Background And Aims: The mechanism of intraduodenal fat induced inhibition of food intake is still unclear. Therefore, we tested the ability of duodenal fatty acids to suppress food intake at a lunchtime meal; in addition, we were interested to test if these effects were mediated by cholecystokinin (CCK) A receptors.

Subjects And Methods: Three sequential double blind, three period crossover studies were performed in 12 healthy males each: (1) subjects received intraduodenal fat with or without 120 mg of tetrahydrolipstatin, an inhibitor of gastrointestinal lipases, or saline; (2) volunteers received intraduodenal long chain fatty acids, medium chain fatty acids, or saline; (3) subjects received long chain fatty acids or saline together with concomitant intravenous infusions of saline or loxiglumide, a specific CCK-A receptor antagonist.

Inhibition of food intake in response to intestinal lipid is mediated by cholecystokinin in humans.

Intraduodenal fat inhibits gastric emptying and exerts early satiation in animals and humans, but it is not clear whether the effects are mediated by cholecystokinin (CCK) in humans. Here, we tested whether CCK-A receptors mediate the inhibition of fat on food intake. Two sequential, double-blind, crossover studies were performed in 24 male subjects.

Flower-enhanced expression of a nuclear-encoded mitochondrial respiratory protein is associated with changes in mitochondrion number.

The mitochondrial Rieske iron-sulfur protein is an obligatory component of the respiratory electron transport chain that is encoded by a single-copy gene in mammals and fungi. In contrast, this protein is encoded by a small gene family in dicotyledonous tobacco and monocotyledonous maize. We cloned four cDNAs from tobacco that encode the mitochondrial Rieske iron-sulfur protein.

Functional analysis in yeast of cDNA coding for the mitochondrial Rieske iron-sulfur protein of higher plants.

cDNA clones coding for the nuclear-encoded mitochondrial Rieske iron-sulfur protein (RISP) have been isolated from maize and tobacco. Complementation analysis of hybrid proteins consisting of different domains of plant and yeast RISPs showed that the carboxyl two-thirds of the plant protein is functionally equivalent to that of the yeast protein. The amino terminus of the RISP, however, seems to be species specific because this region is not interchangeable between plant and yeast proteins.

The ATPase subunit 6 gene of tobacco mitochondria contains an unusual sequence.

We have isolated and characterized the F0-ATPase subunit 6 gene (atp6) from tobacco mitochondria. The tobacco sequence exists as a single copy, is transcribed and contains an open reading frame (ORF) capable of encoding a peptide of 395 amino acids. The first 130 amino acids of the tobacco putative polypeptide show limited homology with the N terminus predicted for the maize ATPase subunit 6.

The tobacco mitochondrial ATPase subunit 9 gene is closely linked to an open reading frame for a ribosomal protein.

A transcribed segment of mitochondrial DNA (mtDNA) from Nicotiana tabacum contains the F0-ATPase subunit 9 gene, an open reading frame with homology to the E. coli small subunit ribosomal protein S13 and an open reading frame with homology to a portion of the mammalian "URF 1" protein, recently shown to be a component of the NADH:ubiquinone reductase complex (NADH:Q 1). The transcriptional patterns of the tobacco ATPase 9 gene and S13-like open reading frame share eight RNA species indicating the two sequences are part of the same transcriptional unit.

Comparison of the mitochondrial genome of Nicotiana tabacum with its progenitor species.

Mitochondrial DNAs from Nicotiana tabacum, an amphiploid, and its putative progenitor species, N. sylvestris and N. tomentosiformis were compared in structure and organization.

Maternal and Reciprocal Effects on Seedling Characters in ARABIDOPSIS THALIANA (L.) Heynh.

Five early growth characters were examined in six races of Arabidopsis thaliana (L.) Heynh, their reciprocal F(1) hybrids (1974) and F(1) by tester hybrids, using a seventh race as a paternal tester. Three of the five characters were also examined at two nutrient levels in reciprocal F(1) hybrids (1972) of all seven races.

Selection for Annual Growth Curves in NICOTIANA TABACUM L.

The cumulative growth of a plant is the result of interrelated processes, and response to selection for changes in the annual growth curve requires many physiological adjustments. Selection to modify the entire annual growth curve may therefore not be as effective as linear models may predict. Periodic growth of a population of Nicotiana tabacum L.

Extranuclear Temperature-Sensitive Lethality in Nicotiana tabacum L.

Tobacco seedlings from progeny of a single aberrant plant, either self-fertilized or used as the female in crosses, failed to become autotrophic at 13 degrees day and 8 degrees night temperatures, but grew normally at 26 degrees day and 20 degrees night temperatures. After initial normal growth at 26 degrees day and 20 degrees night temperatures, autotrophic plants from the aberrant line also died after subsequent exposure to 13 degrees day and 8 degrees night temperatures. The temperature-sensitive lethality was transmitted only through the female parent.

Selection for fresh weight in Arabidopsis thaliana under two mating systems.

Four races of Arabidopsis thaliana were used to produce two F 2 populations and these constituted the base populations of an artifical selection study. All plants were grown under aseptic culture conditions in a controlled environment and the character studied was fresh weight after 15 days' growth. For one section of the study, two selection intensities were applied to each F 2 population and the selected parents were randomly mated.