Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| a family outbreak of serious streptococcal infection. | a localized outbreak of scarlet fever was caused by an m-nontypable t-1 (nt/1) group a beta-hemolytic streptococcus. the result was a fatal outcome in a 5-year-old child and a near fatality in his 10-year-old sibling. the outbreak was confined to family units that had members with whom the children were close playmates. extensive epidemiologic studies in neighborhood schools and local hospital emergency rooms did not demonstrate a disemination of the causative serotype in the community. | 1976 | 781335 |
| physiology and ecology of bacteriophages of the marine bacterium beneckea natriegens: salinity. | the effects of variation in ionic levels on the stability and replication of two bacteriophages (nt-1 and nt-6) host specific for the marine bacterium beneckea natriegens were examined. monovalent cations influenced the adsorption of the nt-1 but not the nt-6 phage; however, one-step growth studies showed that nacl was required for replication of both phage. the nacl optimum for nt-1 production was 0.25 m nacl, the same as the growth optimum for b. natriegens. however, the optimum for nt-6 produ ... | 1976 | 938035 |
| changes in membrane lipid composition during temperature adaptation by a thermotolerant strain of tetrahymena pyriformis. | experiments on temperature adaptation have been conducted using a thermotolerant clone of tetrahymena pyriformis designated as strain nt-1. the strain was able to grow well at 39.5 and 15 degrees c and could adapt quickly when transferred from one of these temperatures to the other. cells grown at the extreme temperatures differed markedly in their membrane lipid composition, particularly in the phospholipid polar head groups and hydrocarbon chains. the levels of fatty acid unsaturation increase ... | 1976 | 817746 |
| tetrahymena strives to maintain the fluidity interrelationships of all its membranes constant. electron microscope evidence. | when cells of tetrahymena pyriformis, strain nt-1, were chilled from their growth temperature of 39.5 degrees c to lower temperatures, the plasma membrane, outer alveolar, nuclear, outer mitochondrial, food vacuolar, and endoplasmic reticulum membranes each responded in a fashion quite characteristic of the membrane type. in most cases a distinctive rearrangement of intramembrane particles, as discerned by freeze-fracture electron microscopy, began abruptly at a definitive temperature. by compar ... | 1977 | 402370 |
| studies on tetrahymena membranes. palmitoyl-coenzyme a desaturase, a possible key enzyme for temperature adaptation in tetrahymena microsomes. | (1) microsomes from a thermotolerant tetrahymena nt-1 catalyze the conversion of palmitoyl-coa to palmitoleate. (2) palmitoyl-coa desaturase enzyme requires molecular oxygen and nadh or nadph as cofactor and its activity is inhibited by cyanide. a ph optimum range 7.0--7.3 is observed. (3) there is a clear break at 30 degrees c and a slight bend around 15 degrees c in the arrhenius plots of palmitoyl-coa desaturase activity. (4) after quenching from 39.5 degrees c, at 26 degrees c microsomal mem ... | 1977 | 20149 |
| a novel tetrahymena sp. with unusual membrane lipid composition, with special reference to iso fatty acyl chains. | a novel tetrahymena sp. is similar in appearance to four classical strains (wh-14, gl, w, nt-1) of t. pyriformis except for a larger width. the phospholipid and acyl chain compositions of membranes of this novel species are significantly different from those of other strains. the tetrahymena sp. has a much higher content of ethanolamine phosphoglyceride and a lower level of glyceroaminoethyl phosphonate. major fatty acids of this strain are iso 15:0 and iso 17:1, which are, if present, usually m ... | 1978 | 107352 |
| mechanism of thermal adaptation of membrane lipids in tetrahymena pyriformis nt-1. possible evidence for temperature-mediated induction of palmitoyl-coa desaturase. | the regulatory mechanism of a key enzyme, palmitoyl-coa desaturase, involved in the adaptation to temperature shift was investigated by labeling tetrahymena pyriformis cells with [14c]palmitic acid. the rate of conversion of [14c]palmitate to [14c]palmitoleate was shown to be dependent on incubation temperature and also to be maximal at 2 h after the shift 39.5 to 15 degrees c. addition of cycloheximide before the temperature shift produced no increase in desaturation of [14c]palmitate after the ... | 1978 | 416850 |
| an ecological study of bacteriophages of vibrio natriegens. | effects of temperature and anaerobic conditions on the replication of two bacteriophages, nt-1 and nt-6, of the estuarine bacterium vibrio natriegens were studied. reduction in temperature resulted in longer latent periods and reduced burst sizes for both phages. replication under anaerobic conditions resulted in longer latent periods; however, phage nt-6 had a reduced burst size, whereas phage nt-1 had an increased burst size, resulting in a rate of phage production nearly equal to that observe ... | 1978 | 647480 |
| membrane changes during growth of tetrahymena in the presence of ethanol. | after a brief lag period for acclimation, tetrahymena pyriformis, strain nt-1, is capable of growing in culture medium containing high levels of ethanol. when grown in a medium having 1.6% ethanol, the membrane phospholipid composition was significantly different from that of control cells. the principal changes included a reduction in hexadecenoic acids (16 : 1 and 16 : 2) from 23% to 5% and an increase in linoleic acid (18 : 2) from 14% to 25% similar but less pronounced changes were observed ... | 1979 | 105757 |
| new serotypes of group b streptococci isolated from human sources. | antisera raised in rabbits against two nontypable group b streptococci, which were not agglutinable in a specific group b antiserum, were tested with acid extracts of 78 nontypable human group b streptococci. one antiserum (12351) reacted with 15 strains, and the other (7271) reacted with only 2 strains. antiserum to wilkinson's strain ss 1169 (nt 1) reacted with three strains. antiserum against strain 12351 appears to be a useful antiserum against a new type antigen, which is probably polysacch ... | 1979 | 115895 |
| studies on cyclic nucleotide metabolism in tetrahymena pyriformis: partial characterization of cyclic amp- and cyclic gmp-dependent phosphodiesterases. | cyclic nucleotide phosphodiesterase [ec 3.1.4.17] was examined in tetrahymena pyriformis strain nt-1. enzymic activity was associated with the soluble and the particulate fractions, whereas most of the cyclic gmp phosphodiesterase activity was localized in the soluble fraction; the activities were optimal at ph 8.0-9.0. although very low activities were detected in the absence of divalent cations, they were significantly increased by the addition of either mg2+ or mn2+. a kinetic analysis of the ... | 1980 | 6109021 |
| the stimulatory effects of neurotensin and related peptides in rat stomach strips and guinea-pig atria. | 1 the stimulatory effects of neurotensin (nt) and several nt fragments were evaluated in two pharmacological preparations: rat stomach strips and isolated spontaneously beating atria of guinea-pigs.2 in rat stomach strips, nt elicited a dose-dependent contractile effect in concentrations varying between 1.3 x 10(-9) and 5.4 x 10(-7) m.3 the contractile effect of nt (1.3 and 5.4 x 10(-8) m) in this tissue was not modified by atropine (3.4 x 10(-7) m), methysergide (2.0 x 10(-6) m), a mixture of c ... | 1980 | 7357202 |
| pharmacological characterization of neurotensin receptors in the rat isolated portal vein using analogues and fragments of neurotensin. | the contractile effects of the tridecapeptide neurotensin (nt) and several nt fragments and analogues were evaluated and compared in the rat isolated portal vein. the removal of the sequence pglu1-leu2-tyr3-glu4-asn5-lys6-pro7 produced practically no change in the myotropic activity of nt while the deletion of leu13 or the last 3 c-terminal amino acids (e.g. tyr11, ile12 and leu13) gave compounds with very low agonist activity (nt(1-12)) or devoid completely of affinity and intrinsic activity (n ... | 1980 | 6252013 |
| isolation, structure and biologic activity of chicken intestinal neurotensin. | using a radioimmunoassay towards bovine neurotensin(nt), chicken nt has been purified to homogeneity from extracts of intestine and its amino acid sequence determined to be: less than glu-leu-his-val-asn-lys-ala-arg-arg-pro-tyr-ile-leu-oh. the molecule is identical to the bovine peptide except for the 3 amino acid substitutions located in its nh2-terminal half and italicized above (his/tyr: val/glu; ala/pro). the structure for chicken nt is consistent with earlier immunochemical studies which in ... | 1980 | 7243616 |
| the strong-migration limit in geographically structured populations. | some strong-migration limits are established for geographically structured populations. a diploid monoecious population is subdivided into a finite number of colonies, which exchange migrants. the migration pattern is fixed and ergodic, but otherwise arbitrary. generations are discrete and nonoverlapping; the analysis is restricted to a single locus. in all the limiting results, an effective population number ne (less than or equal to nt) appears instead of the actual total population number nt. ... | 1980 | 7365330 |
| effects of neurotensin and neurotensin analogues on the migrating myoelectrical complexes in the small intestine of rats. | the purpose of the present experiments was to study the effect of neurotensin and neurotensin analogues on the migrating myoelectrical complexes in the small intestine of rats. four bipolar electrodes were implanted into the muscular wall of the small intestine. the electrodes were placed 5, 15, 25 and 35 cm distal to the pylorus. 7-10 days after the operation the animals were fasted for 48 h with free access to water. some experiments were performed on conscious rats and in others the rats were ... | 1981 | 7315414 |
| high performance liquid chromatographic analysis of catecholamines in growing and non-growing tetrahymena pyriformis. | tetrahymena pyriformis, strains nt-1 and w, harvested in logarithmic (growing) and stationary (non-growing) phases, were found by high-performance liquid chromatography to contain considerable quantities of dopamine. in addition, small amounts of epinephrine and norepinephrine were detected. logarithmic-phase strain nt-1 cells contained 249 +/- 44 pg dopamine/10(6) cells compared to 477 +/- 42 pg/10(6) cells for logarithmic-phase strain w cells for logarithmic-phase strain w cells. the dopamine ... | 1981 | 6789887 |
| neurotensin blocks certain amphetamine-induced behaviours. | bilateral injections of either neurotensin (nt; 0.3, 1 or 5 micrograms in 1 microliter artificial csf) or haloperidol (ha; 2.5 or 5 micrograms in 1 microliter 0.3% tartaric acid) into nucleus accumbens of rats markedly diminished the forward locomotion and rearing induced by d-amphetamine (am; 2 mg per kg, ip). neither nt nor ha affected the insomnia or sniffing component of am arousal. isovolumetric intra-accumbens injections of artificial csf or the endogenous decapeptide, luteinizing hormone- ... | 1981 | 7231526 |
| isolation and characterization of two new trichothecenes from fusarium sporotrichioides strain m-1-1. | two new trichothecenes were isolated along with t-2 toxin, neosolaniol, and ht-2 toxin from the culture filtrate of fusarium sporotrichioides strain m-1-1. the structures of the new toxins were characterized to be 4 beta, 8 alpha-diacetoxy-12,13-epoxytrichothec-9-ene-3 alpha, 15-diol (designated nt-1) and 4 beta-acetoxy-12,13-epoxy-trichothec-9-ene-3 alpha,8 alpha,15-triol (designated nt-2). | 1981 | 7294786 |
| subcellular distribution of calmodulin and calmodulin-binding sites in tetrahymena pyriformis. | the subcellular distribution of calmodulin and particulate calmodulin-binding activity was studied in a eukaryotic protozoan, tetrahymena pyriformis nt-1. the particulate calmodulin-binding activity was found to be localized principally in microsomes and to some extent in cilia and surface membranes called pellicles. nearly all (93%) of the total amount of calmodulin was recovered in two soluble compartments, the ciliary and postmicrosomal supernatant fractions. | 1981 | 6796570 |
| studies on thermal adaptation in tetrahymena membrane lipids. changes in positional distribution of fatty acids in diacyl-phospholipids and alkyl-acyl-phospholipids during temperature acclimation. | the positioning of acyl chains in both 1-o-alkyl-2-acyl- and 1,2-diacyl-phospholipids was analyzed at various time intervals for a thermotolerant strain (nt-1) of tetrahymena pyriformis cells during cold acclimation. during the 10 h period of adaptation, cells were not able to grow but maintained the ability to divide. the content of palmitate (16 : 0) in phosphatidylcholine and phosphatidylethanolamine was decreased after temperature-shift, with a concurrent increase of palmitoleate (16 : 1 del ... | 1981 | 6793077 |
| changes in hemoprotein content in tetrahymena pyriformis (strain nt-1) as studied by low temperature spectroscopy. | 1982 | 6802811 | |
| studies on thermal adaptation in tetrahymena membrane lipids. modification of positional distribution of phospholipid acyl chains in plasma membranes, mitochondria and microsomes. | the positional distribution of fatty acyl chains in major glycerophospholipids (phosphatidylethanolamine, phosphatidylcholine and 2-aminoethylphosphonolipid) of three membrane fractions (plasma membranes, mitochondria and microsomes) of the thermotolerant tetrahymena pyriformis nt-1 cells was analyzed at various time intervals within 10 h after a temperature shift from 39 to 15 degrees c. during this period of acclimation there were no changes in both the total phospholipid content and its propo ... | 1982 | 6807352 |
| regulation of mast cell histamine release by neurotensin. | neurotensin (nt), a neuropeptide found both centrally and peripherally, stimulated release of histamine from rat peritoneal mast cells in a dose-dependent manner. release was evident by 10 nm and reached a plateau of 15-20% total cellular histamine by 10(-7)-10(-6) m nt. optimal conditions for stimulation occurred at ph 6.5-7.5, 37 degrees c and at calcium concentrations of less than 1 mm. release was complete within 2 minutes of peptide addition. studies of histamine release by nt analogues ind ... | 1982 | 6182435 |
| enhancement of phagocytosis by neurotensin, a newly found biological activity of the neuropeptide. | specific binding of neurotensin (nt) to mouse peritoneal thioglycollate-elicited macrophages and macrophages differentiated in vitro from bone marrow cells was demonstrated and characterized. nt binding to these phagocytes modulated their phagocytic capacity in a biphasic manner. at concentrations of 10(-14) to 10(-9) m nt, a dose-dependent augmentation of phagocytosis (up to 2-fold) was observed. further increases in the concentration of nt resulted in a gradual decrease of the augmented respon ... | 1982 | 6186124 |
| elevation of plasma neurotensinlike immunoreactivity after a meal. characterization of the elevated components. | the detection of an elevation in neurotensinlike immunoreactivity in peripheral plasma for several hours after a meal has been confirmed and shown to be primarily due to the presence of aminoterminal fragments of neurotensin (nt) rather than to nt itself. we have developed a procedure to separate and characterize these n-terminal cross-reacting substances, and to estimate the contributions of these constitutents to plasma neurotensinlike immunoreactivity. gel chromatography of pooled plasma extr ... | 1982 | 7085889 |
| increase in dopamine metabolites in rat brain by neurotensin. | neurotensin (nt), an endogenous tridecapeptide, is heterogeneously distributed in the central nervous system. the present study examined the effects of physiologically and behaviorally active doses of nt (1--100 micrograms intracisternally) on dopamine, serotonin and their primary metabolites as well as accumulation of dopa after inhibition of dopa decarboxylase. nt was shown to increase dopa accumulation when compared with saline treatment, suggesting that dopamine synthesis was increased. in a ... | 1982 | 6811728 |
| changes in particulate-bound protease activity during cold acclimation in tetrahymena pyriformis. | the protease activity, as assayed at ph 8.0 with azocasein as substrate, of a ciliate protozoan tetrahymena pyriformis nt-1, was found to alter by growing the cells at various constant temperatures or at shifted temperatures. the intracellular protease activity, when cells were grown at either constant 39 degrees c or 15 degrees c, was decreased throughout the growth phase with significant secretion into the medium. on the other hand, when the culture temperature was transferred from 39 degrees ... | 1982 | 6816294 |
| planar brownian motion in the presence of an attractive force. | the two-dimensional brownian motion of circular disks is considered where these join to form groups whenever they touch. the total number of groups nt is considered as a function of time. an upper bound for nt-1 is derived and compared to the experimental movement of erythrocytes. cells at ph = 7.4 and ph = 6.3 are shown to have a group count that respectively exceeds and falls below the plotted bound. this provides evidence that live cells have a tendency to coalesce that is not explained by br ... | 1983 | 6199112 |
| effects of endurance training on coronary resistance in dogs. | the effects of endurance training on coronary vascular resistance, myocardial blood flow, and oxygen consumption during tachycardia, and with adenosine-induced coronary dilation, were studied in a group of exercise-trained dogs. seven mongrel dogs were conditioned by 8 wk of running on a motor-driven treadmill. following conditioning, aortic pressure was unchanged in trained compared to a nontrained group, while cardiac output was somewhat lower in the trained group. left ventricular myocardial ... | 1983 | 6645861 |
| release of histamine and adrenaline in vivo following intravenous administration of neurotensin. | plasma histamine levels of rats anesthetized with pentobarbital sodium were significantly increased by intravenous administration of neurotensin (nt, 1 nmole/kg) with the maximum effect at 3 min, and a return to the initial levels in 20 min. treatment of animals with compound 48/80 or disodium cromoglycate completely inhibited the elevation of histamine level by nt, however, treatment with reserpine or diphenhydramine and adrenalectomy did not affect the elevation. plasma adrenaline levels incre ... | 1983 | 6405112 |
| evidence for a vertical displacement of intramembranous particles on the plasma membrane of tetrahymena cells by a local anesthetic. | we examined the effect of a local anesthetic, dibucaine, on the plasma membrane of tetrahymena pyriformis strain nt-1 using freeze-fracture electron microscopy. intramembranous particles (imps) were distributed homogeneously on the plasma membrane of untreated cells. but, when tetrahymena cells had been treated with 1.3 mm dibucaine for 5 min at growth temperature, freeze-fracture micrographs of the plasma membrane showed marked alterations. although imps showed an almost homogeneous distributio ... | 1983 | 6421494 |
| neurotensin: a modulator of enteric cholinergic neurons in the guinea pig small intestine. | release of [3h]acetylcholine was studied in the presence of neurotensin (nt) on the myenteric plexus-longitudinal muscle strips (mplm) from the guinea pig small intestine. in the dose range from 3 pm to 3 nm, nt induced a dose-related increase in the efflux of [3h]acetylcholine from the mplm. this release was completely inhibited by 1.5 x 10(-6) m tetrodotoxin. the output of acetylcholine evoked by nt (7.5 x 10(-11) m) was significantly depressed by the addition of somatostatin (6.1 x 10(-7) m) ... | 1983 | 6140179 |
| neurotensin: effects of hypothalamic and intravenous injections on eating and drinking in rats. | to investigate a role for the brain-gut peptide neurotensin (nt) in ingestive behavior, changes in food and water intake of food-deprived rats were examined following injection of nt into the paraventricular hypothalamic nucleus (pvn) or the mesenteric vein. unilateral pvn nt (2.5, 5.0, 10.0 micrograms/0.3 microliter) produced substantial dose-dependent reductions in total food intake 0.5, 1, and 4 hr postinjection. in contrast, pvn nt had no effect on water intake and produced no change in groo ... | 1983 | 6685868 |
| relation between lower esophageal sphincter (les) pressure and the plasma concentration of neurotensin during intravenous infusion of neurotensin(1-13) and (gln4)neurotensin(1-13) in man. | ingestion of fat causes a pronounced decrease in lower esophageal sphincter (les) pressure. this may be due in part to effects of neurotensin (nt), which is released postprandially after the ingestion of fat. the aim of the present investigation was to establish whether the les pressure decreases at physiological plasma concentrations of nt(1-13). in addition, we have compared the effects and metabolism of nt(1-13) and (gln4)nt(1-13). the experiments were performed in 3 healthy male volunteers w ... | 1983 | 6578671 |
| characterization of human plasma neurotensin-like immunoreactivity after fat ingestion. | the concentration of neurotensin-like immunoreactivity in plasma (p-ntli) increases after the ingestion of food, and fat seems to be the most important nutrient. it is essential to characterize the nt species that are responsible for this postprandial rise of p-ntli. after an overnight fast, two male and two female subjects therefore ingested 300 ml of cream (containing 40% (w/w) milk fat). unextracted plasma samples were subjected to column chromatography and the eluates were analysed using fou ... | 1983 | 6622752 |
| organ and plasma metabolism of neurotensin in sheep. | the metabolism of neurotensin (nt) across specific vascular beds of conscious sheep and the stability of nt in plasma have been quantitated. the nature of the metabolites has been characterized with region-specific antiserums and chromatography. nt-(1-13) was infused at 200 pmol x kg-1 x h-1 for 60 min into nine ewes, and blood samples were taken via cannulas in the aorta, pulmonary artery, portal vein, hepatic vein, renal vein, and jugular vein. two antiserums, one directed towards the n-termin ... | 1983 | 6638173 |
| cell characterization and phorbol ester-induced differentiation of a human acute lymphoblastic leukemia cell line (nt-1). | 1984 | 6594897 | |
| the metabolism of intravenously infused neurotensin in man and its chromatographic characterization in human plasma. | the metabolism of iv infused neurotensin (nt) was studied and its disappearance half-time compared with that of infused n-terminal octapeptide of nt 1-8 in six normal subjects by ria with antisera directed against the c- and n-terminal regions of the nt molecule. the disappearance half-time of nt in circulating plasma was 1.4 min measured with the c-terminal antibody and 6.0 min measured with the n-terminal antibody. the disappearance half-time of nt 1-8 was 30 min measured with the n-terminal a ... | 1984 | 6725524 |
| cerebrospinal fluid lactate and pyruvate concentrations in patients with malignant hypertension. | lactate and pyruvate concentrations and acid-base parameters in cerebrospinal fluid (csf) and arterial blood were measured in 21 patients with malignant hypertension ( mht ), 19 with benign hypertension (bht) and 21 normotensive subjects (nt). average values for csf lactate and lactate/pyruvate (l/p) ratio were significantly higher in mht (1.90 +/- 10 mm/1, 19.2 +/- 1.0) than in either bht (1.50 +/- 0.05 mm/l, 15.7 +/- 0.7) or nt (1.44 +/- 0.04 mm/1, 15.7 +/- 0.4). there was a linear correlation ... | 1984 | 6737011 |
| effect of the local anesthetic dibucaine on the surface membrane in sterol-manipulated tetrahymena pyriformis studied by freeze-fracture electron microscopy. | the effect of the local anesthetic dibucaine on the membrane ultrastructure of sterol-manipulated tetrahymena pyriformis (nt-1 strain) was studied by freeze-fracture electron microscopy. dibucaine-treated, ergosterol-replaced tetrahymena cells had marked alterations in their plasma membranes. imp-free small depressions (exoplasmic fracture face) and protrusions (protoplasmic fracture face) were formed on the plasma membranes which was in contact with the outer alveolar membrane. in addition, lar ... | 1984 | 6442214 |
| influence of histamine and prostaglandin on desensitization to neurotensin in rat blood pressure. | triphasic depressor-pressor-depressor blood pressure responses to neurotensin (nt: 1.67 micrograms/kg i.v.) in anesthetized rats were not elicited when the second dose of nt was administered 20 min after the first injection. pretreatment of animals with histamine markedly reduced the depressor response to nt, and vice versa. the triphasic blood pressure pattern remained unaffected with acetylcholine and serotonin treatment, and hypotensive effects of acetylcholine and serotonin were not modified ... | 1984 | 6493455 |
| adsorption of tumorigenic agrobacterium tumefaciens cells to susceptible potato tuber tissues. | cells of tumorigenic agrobacterium tumefaciens strain b6 were labeled with [35s]methionine and used to estimate bacterial adsorption to potato tuber discs. after 10 min at ph 7.2, about 5 x 10(5) bacteria adsorb to each 9.0-mm disc. lengthening the incubation period to 90 min increases adsorption to about 11 x 10(5) bacteria per disc. bacterial adsorption is reduced under both alkaline and acid ph conditions and increases 2.3-fold if the number of bacterial cells in the inoculum is doubled. adso ... | 1984 | 6498639 |
| characterization of a pancreatic tumor containing vasoactive intestinal peptide, neurotensin, and pancreatic polypeptide. | the biochemical characteristics of a pancreatic tumor from a patient with watery diarrhea, hypokalemia, hypochlorhydria, and steatorrhea is described plasma concentrations of vasoactive intestinal peptide (vip) were elevated 6-fold, those of neurotensin (nt) were elevated 10-fold, and those of pancreatic polypeptide (pp) were elevated 200-fold above the normal range. the pancreatic tumor removed was found to contain high concentrations of these peptides in a similar ratio to plasma. the tumor co ... | 1984 | 6315763 |
| thermoadaptive regulation of microsomal desaturase and electron-transport enzyme activities in lipid-manipulated tetrahymena cells. extent of unsaturated fatty acid production is dependent on membrane fluidity before temperature down-shift. | exposure of tetrahymena pyriformis nt-1 to chimyl alcohol (1-o-hexadecyl glycerol) produced a reproducible enhancement in unsaturated fatty acids and a great decrease in order parameter (s), which result from the 2-fold increases of stearoyl-coa and oleoyl-coa desaturase activities in microsomes. when the chimyl alcohol-fed cells were shifted from 34 to 15 degrees c (down-shift), unlike the drastic increases in palmitoyl-coa, stearoyl-coa and oleoyl-coa desaturase activities in the native cells, ... | 1984 | 6422990 |
| on the formation of alpha-hydroxy fatty acids. evidence for a direct hydroxylation of nonhydroxy fatty acid-containing sphingolipids. | when tetrahymena pyriformis, strain nt-1, was warmed from a growth temperature of 15 degrees c to 39 degrees c, there was a rapid conversion of its sphingolipids from the nonhydroxy fatty acid-containing ceramide aminoethylphosphonate (ncaep) predominant at low temperature to the alpha-hydroxy fatty acid-containing analog (hcaep). the fatty acid composition of the freshly formed hcaep strongly resembled that of the original ncaep pool. an extensive utilization of ncaep long chain bases for hcaep ... | 1984 | 6423633 |
| temperature-induced changes in the hydroxy and non-hydroxy fatty acid-containing sphingolipids abundant in the surface membrane of tetrahymena pyriformis nt-1. | sphingolipids make up 30 to 40 mole % of the phospholipids found in the surface membrane of tetrahymena pyriformis nt-1. we have identified the two major classes as non-hydroxy fatty acid-containing ceramide-2-aminoethylphosphonate (ncaep) and alpha-hydroxy fatty acid-containing ceramide-2-aminoethylphosphonate (hcaep). both classes were well represented in cells grown at 39 degrees c. at this temperature their principal long chain bases were n-hexadeca-4-sphingenine and n-nonadeca-4-sphingenine ... | 1984 | 6423752 |
| metabolism of neurotensin and pancreatic polypeptide in man: role of the kidney and plasma factors. | neurotensin (nt) is a 13 amino acid peptide found predominantly in the ileum and it is released into the circulation by a meal. much of the circulating nt consists of n terminal fragments which have no known biological activity. however, the sites and rates of nt metabolism are not known. in the present study the mcr and half-disappearance time of nt were estimated by infusing nt(1-13) into 10 normal subjects. the role of the kidney was assessed by studies in patients with chronic renal failure ... | 1984 | 6707191 |
| occurrence, storage and release of neurotensin-like immunoreactivity from the adrenal gland. | in the present study we have investigated the presence of radioimmunoassayable neurotensin-like immunoreactivity (ntli) in extracts of adrenal glands from hen, guinea-pig, rat, cat, dog and man. in addition, gel filtration chromatography and studies on the storage site of ntli, using subcellular fractionation techniques, were performed. finally, ntli release in relation to noradrenaline (na) from cat adrenal glands upon splanchnic nerve activation was studied in vivo. in all species investigated ... | 1984 | 6741572 |
| participation of mast cell 5-hydroxytryptamine in the vasoconstrictor effect of neurotensin in the rat perfused hindquarter. | neurotensin (nt) (1 x 10(-8) - 1.5 x 10(-6) g ml-1) caused a transient, dose-dependent increase in perfusion pressure in the rat perfused hindquarter. the vasoconstrictor effect of nt was associated with a short-lived, dose-dependent release of histamine and 5-hydroxytryptamine (5-ht) in the hindquarter effluent. compound 48/80, a classical mast cell secretagogue, also elicited a vasoconstrictor effect in, and release of histamine from, the rat hindquarter. the vasoconstrictor effect and the rel ... | 1984 | 6422173 |
| role of neurotensin in pancreatic secretion. | the objective of this study was to examine the effect of neurotensin (nt) on pancreatic exocrine secretion in awake dogs (n = 5) with chronic gastric and pancreatic fistulas. intravenous (iv) infusion of nt (1 microgram/kg/hr) alone significantly stimulated pancreatic secretion of protein and bicarbonate without causing release of secretin or cholecystokinin-33 (cck-33). iv nt potentiated the secretory response of pancreatic bicarbonate to the intraduodenal (id) infusion of hcl alone and to id i ... | 1984 | 6463855 |
| catabolism of neurotensin in interstitial fluid of the rat stomach. | the catabolism of neurotensin (nt) was studied in the gastric submucosa of the conscious rat using a novel technique to obtain a dialysate of interstitial fluid. a microdialysis fiber system was surgically implanted into the gastric submucosa, and 2 days later experiments were commenced on conscious animals. isotope-labeled nt was administered to the tissue, and a dialysate of the submucosal interstitial fluid was collected. in the dialysate, nt and catabolites of nt formed in the interstitial f ... | 1984 | 6742119 |
| characterization of mouse lymphoma cells with altered nucleoside transport. | a mutant clone (nt-1) of a t-cell lymphoma was selected for its ability to grow in hat medium (hypoxanthine, aminopterin and thymidine) in the presence of the nucleoside transport inhibitor p-nitrobenzyl-6-mercaptoinosine (nbmi). nt-1 cells contain half the number of nbmi binding sites present on the parental s49 cells and are partially able to transport nucleosides in the presence of the transport inhibitor (nbmi). these observations suggest that the mutant cells are heterozygous for nucleoside ... | 1985 | 3988815 |
| intracellular phospholipase activities of tetrahymena pyriformis. | phospholipase activity was studied in the protozoan tetrahymena pyriformis nt-1 by using exogenous phosphatidylethanolamine and phosphatidylcholine. several phospholipase activities were found in tetrahymena homogenates. they were distinguished with respect to ph optimum, activity dependence on ca2+, substrate specificity and positional specificity. ca2+-dependent phospholipase activity had an optimal ph around 9 and gave rise to free fatty acid and lysophospholipid. this enzyme hydrolyzes phosp ... | 1985 | 3928611 |
| further studies of dopamine metabolism and function in tetrahymena. | the large amounts of dopamine accumulated by cells of tetrahymena pyriformis strain nt-1 and secreted into their growth medium were found to depend primarily upon an extracellular, non-enzymatic conversion of tyrosine to l-dihydroxyphenylalanine (l-dopa); l-dopa was then rapidly taken into the cells and transformed into dopamine enzymatically. efforts to find physiologically significant dopamine binding sites on the cell surface or dopamine-sensitive adenylate cyclase activity were unsuccessful, ... | 1985 | 3921697 |
| comparison of the immunochemical responses by anti-nadph-cytochrome c reductase of tetrahymena pyriformis (strain nt-1) in protozoan cells and mammalian liver microsomes. | comparison of the microsomal nadph-cytochrome c reductase activities in the four tetrahymena cells (pyriformis, strain gl and nt-1; thermophilia; iso) and rat liver was studied. the reductase activity in strain nt-1 was lowest among four tetrahymena cells grown at 24 degrees c. rabbit antibody was prepared against the purified nadph-cytochrome c reductase from tetrahymena pyriformis (strain nt-1) microsomes. microsomal nadph-cytochrome c reductase activities in various tetrahymena cells were inh ... | 1985 | 3922671 |
| effects of intraventricular neurotensin on blood pressure and heat balance in rats. | the effects of intraventricular neurotensin (nt) at doses of 0.1, 1.0, and 10.0 micrograms on blood pressure (bp), heart rate (hr), heat production (m), heat loss (h), and colonic temperature (t co1) were investigated in conscious rats in a direct calorimeter at 18 and 28 degrees c. at 18 degrees c, a 10.0 micrograms of nt significantly increased bp for several minutes after injection with prolonged bradycardia. the larger two doses (1.0 and 10.0 micrograms) significantly reduced m and t co1. in ... | 1985 | 4046236 |
| the effect of nephrectomy and ureter ligation on plasma neurotensin-like immunoreactivity levels in the conscious rat. | the effect of nephrectomy and ureter ligation on the concentration of endogenous plasma neurotensin-like immunoreactivity (p-ntli) was studied in conscious rats by means of antiserum 17-8201 which detects nt (1-13) only, and antiserum 0-7709 which detects nt(1-13) and nt(1-8). the unstimulated p-ntli concentration did not change significantly during a 25-h observation period following nephrectomy in comparison with sham operation. however, stimulation of the release of ntli by intraduodenal admi ... | 1985 | 4061110 |
| [11c-methionine pet, imp-spect, ct and mri in brain tumors]. | 11c-labelled l-methionine uptake was measured in 7 patients with brain tumours prior to surgery, and in 2 patients with infarction, using pet. the strongest uptake occurred in tumours with a high grade of malignancy (astrocytoma iv: tumour/non-tumour t/nt = 2.6) while low-grade tumours accumulated less activity (astrocytoma ii: t/nt = 1.4). conventional 99mtc dtpa scans revealed a damage of blood brain barrier (bbb) in 4 patients (2 infarctions) with no or only slight 11c-methionine accumulation ... | 1985 | 2992024 |
| a possible cyclic amp-mediated regulation of microsomal fatty acyl-coa desaturation system in tetrahymena microsomes. | profound alterations in the microsomal fatty acyl-coa desaturase activities and cyclic amp production of a unicellular eukaryote, tetrahymena pyriformis nt-1, originally grown in the glucose-deficient medium, were observed, following the administration of glucose or beta-adrenergic agonists such as epinephrine and isoproterenol. there was a great increase of stearoyl-coa (delta 8) desaturase activity coincident with a 2-fold decrease of oleoyl-coa (delta 12) desaturase activity over the first 2 ... | 1985 | 2861855 |
| alcohol and fatty acid stimulation of neurotensin release from rat small intestine. | we have previously reported that neurotensin (nt) is released from the small intestine and elevated in the hepatic-portal circulation in response to the perfusion of the small intestine with a micellar solution of oleic acid. in order to determine the minimum acyl chain length and whether the presence of a carboxylic acid is necessary for the stimulation of nt release, the small intestine of anesthetized rats was perfused with test solutions of fatty acids of 2-, 4-, 8-, or 18-carbons or fatty a ... | 1985 | 3971900 |
| mapping the 5' ends, 3' ends, and splice sites of mrnas from the early e3 transcription unit of adenovirus 5. | using nuclease gel analyses, the sites in the approximately 4000 nucleotide (nt) e3 transcription unit of adenovirus 5 (ad5) that encode the 5' ends, 3' ends, and 5' and 3' splice sites of the approximately 10 e3 mrnas were determined. transcription initiation of all mrnas occurs at two major (nt 1 and 8) and approximately two minor sites, situated 20-30 nt 3' to a tata box. there are two major 3' end sites (nt 2227 and 3308), located approximately 20 nt downstream from attaaa and an aataaa sequ ... | 1985 | 3966299 |
| inhibition of neurotensin release by a cyclic hexapeptide analog of somatostatin. | studies were performed to determine whether the cyclic hexapeptide analog of somatostatin, cyclo(n-me-ala-tyr-d-trp-lys-val-phe) ii, could alter circulating levels of neurotensin (nt) and inhibit the release of nt from small intestine following the intraluminal perfusion of lipid and etoh. the small intestine of anesthetized rats was perfused with 0.9% nacl, 1mm etoh, 100 mm etoh or 1 mm oleic acid with and without the intravenous infusion of the somatostatin analog. plasma samples collected fro ... | 1985 | 2867526 |
| meal-stimulated neurotensin immunoreactivity in plasma following gastric surgery: characterisation with two region-specific antisera. | plasma neurotensin (nt) response to a simple fatty meal, administered via an indwelling naso-gastric tube, has been assessed in two groups of subjects following gastric surgery without resection, and in healthy controls. two region-specific nt antisera were employed in the radioimmunoassay (ria) of plasma samples. the first, nt3, recognises only nt 1-13 in plasma extracts, while the second, gnt 21, recognises nt 1-13, nt 1-11 and nt 1-8 equally. in addition, plasma extracts were subjected to rev ... | 1986 | 2419192 |
| selective cleavage of human acth, beta-lipotropin, and the n-terminal glycopeptide at pairs of basic residues by ircm-serine protease 1. subcellular localization in small and large vesicles. | we present a study of the cleavage specificity of ircm-serine protease 1 from frozen porcine pituitary neurointermediate lobes using polypeptide substrates representing different segments of human pro-opiomelanocortin. using 125i-labeled acth(11-24) and a 125i-labeled model beta-lipotropin (beta-lph) peptide, the preference of this protease for cleavage c-terminal to the pairs of basic residues lys-arg and lys-lys was clearly seen. this study was extended to larger unlabeled natural human polype ... | 1986 | 3015945 |
| [teratological test of 10% nitroglycerin (nt-1 ointment) in rabbits]. | a teratological test of 10% nitroglycerin (nt-1 ointment) was carried out in new zealand white rabbits. pregnant rabbits were treated percutaneously with nt-1 ointment from day 6 to 18 of gestation at dose levels of 15, 60 and 240 mg/kg/day as nitroglycerin itself. all pregnant rabbits were killed on day 29 of gestation, and the influences of nt-1 ointment upon the performances of dams and fetuses were examined. during the treatment period, erythema was observed on the treated dorsal skin in all ... | 1986 | 3093692 |
| ion permeability of ciliary membrane vesicles isolated from tetrahymena. single-channel recording study on the membrane reconstituted into a planar lipid bilayer. | an ion channel in ciliary membrane vesicles isolated from tetrahymena pyriformis nt-1 was characterized with a single-channel recording technique applied to the membrane reconstituted into a planar lipid bilayer made of soybean phospholipid. the gating of this channel is independent of membrane potential and it spends most of the time in its open-channel state. it is selective for metal cations over gluconate anion although it little distinguishes cations, ca2+, ba2+, mg2+, and k+. this channel ... | 1986 | 2437103 |
| properties of acid phospholipases in lysosome and extracellular medium of tetrahymena pyriformis. | phospholipase activity in the lysosomes of the protozoan tetrahymena pyriformis strain nt-1 was studied using phospholipids radioactively labeled in the fatty acid moieties. lysosomal homogenates showed high phospholipase activity with an acidic ph optimum. unlike the phospholipases in rat liver lysosomes, almost all activity was recovered from the membranous fraction of the lysosomes. the activity was partially solubilized by treatment of the membranes with a detergent or trypsin. using specifi ... | 1986 | 3082863 |
| chromatographic and immunochemical characterization of neurotensin in cat adrenal gland and its release during splanchnic nerve stimulation. | a subpopulation of norepinephrine-containing cells in the cat adrenal medulla contain neurotensin (nt) immunoreactive material. using high performance liquid chromatography (hplc) and radioimmunoassay with region-specific antisera we have demonstrated that electrical stimulation of the splanchnic nerve releases nt and its metabolites nt(1-8) and nt(1-12) from cat adrenal gland into the circulation. blood samples from anesthetized cats were simultaneously collected from the adrenolumbar vein and ... | 1986 | 3736783 |
| [percutaneous chronic toxicity study of 10% nitroglycerin (nt-1 ointment) in rabbits]. | a chronic toxicity test of 10% nitroglycerin (nt-1 ointment) was carried out in male nzw rabbits. nt-1 ointment was applied to the back skin for 26 weeks at daily doses of 15, 60 and 240 mg/kg as nitroglycerin itself, and 5-week withdrawal period was followed. topical dermal responses to nt-1: macroscopically, erythema, edema, scales, papules and dermal thickening were observed in response to nt-1 ointment. in the withdrawal period, however, all of them disappeared. histopathologically, thickeni ... | 1986 | 3093691 |
| nutritional support team vs nonteam management of enteral nutritional support in a veterans administration medical center teaching hospital. | one hundred one patients receiving enteral nutritional support (ens) by tube feeding during a 5-month period were prospectively studied. fifty patients were managed by a nutritional support team (t) and 51 patients were managed by the nonteam approach (nt). demographics, primary diagnosis, chronic diseases, medical service, calculated basal energy expenditure (bee), duration of ens, and final patient disposition were recorded. enteral formula, formula modifications, results of laboratory tests a ... | 1986 | 3099009 |
| [acute toxicity test on dermal application of nt-1 tape and 10% nitroglycerin (nt-1 ointment)]. | an acute toxicity of nt-1 tape was investigated in mice, rats and rabbits, and also an acute toxicity of nt-1 ointment in rabbits. an irritation of nt-1 tape was investigated in rabbits. dead animals treated with nt-1 tape or ointment were not observed in reliable maximum administration dose of 0.88 mg/body as gtn (nitroglycerin) in mice (male; about 29.1 mg/kg, female; about 35.2 mg/kg), of 3.96 mg/body as gtn in rats (male; about 26.0 mg/kg, female; about 28.9 mg/kg) and of 480 mg/kg as gtn in ... | 1986 | 3093689 |
| [percutaneous subacute toxicity study of 10% nitroglycerin (nt-1 ointment) in rabbits]. | nt-1 ointment is a compound containing 10% nitroglycerin which is topically applied to the skin for angina pectoris. the subacute toxicity of this compound was examined by the continuous application for 5 weeks to the shaven skin of rabbit back at dose levels of 240, 120 and 60 mg/kg, and the recovery was examined 3 weeks after withdrawal of the drug. no special skin response to the nt-1 ointment was observed other than an erythema of the grading 2-3 draize points, while the control ointment, wh ... | 1986 | 3093690 |
| neurotensin excites neurons in the arcuate nucleus of the rat hypothalamus in vitro. | the effects of neurotensin (nt) on 41 spontaneously active neurons in the rat hypothalamic arcuate nucleus (arc) were determined using an in vitro brain slice technique. addition of nt (1 microm to 10 nm) to the perifusing medium allowed the action of known concentrations of nt to be examined. concentrations of peptide greater than 10 nm evoked excessive depolarization of sensitive neurons resulting in long periods of postexcitatory inhibition. at 10 nm, nt evoked reversible and repeatable excit ... | 1986 | 3947977 |
| effect of neurotensin and neurotensin fragments on gastric acid secretion in man. | the effect of intravenous infusion of neurotensin (nt) and nt-fragments on pentagastrin stimulated gastric acid secretion was investigated in healthy subjects. neurotensin was infused in three doses (72, 144 and 288 pmol/kg per h). an n-terminal fragment (nt 1-8), a c-terminal fragment (nt 8-13) and an nt-analogue, substituted at the c-terminal tyrosine residue (phe11-nt) were infused in two doses (72 and 144 pmol/kg per h). concentrations of the infused peptides were measured in peripheral veno ... | 1986 | 3763961 |
| neurotensin stimulates [3h]oleic acid translocation across rat small intestine. | the effect of neurotensin (nt) on the translocation of intraluminally administered lipid across the duodenum as well as across the entire length of the small intestine was studied in the rat. in the first series of experiments, the appearance in the lymph of [3h]oleic acid instilled as a bolus into a segment of the duodenum was followed for 3 h. infusion of nt (0.6 pmol x kg-1 x min-1) via the superior mesenteric artery resulted in a significant increase in the appearance of label in the lymph w ... | 1986 | 3789148 |
| unusual transcripts in la crosse virus-infected cells and the site for nucleocapsid assembly. | the la crosse virus s genome segment is known to code for two plus-strand transcripts, free s-mrna (nucleotide [nt] -15 to 886) and encapsidated antigenome rna (nt 1 to 983). early in infection only these plus-strand transcripts could be detected, but at later times plus-strand rnas representing nt 1 to 886 in an encapsidated form and nt -15 to 983 as a free rna could also be seen, as well as s-mrna in an encapsidated form. the encapsidated s-mrna became relatively important at later times becau ... | 1987 | 3806796 |
| distribution of neurotensin receptors in the primate hippocampal region: a quantitative autoradiographic study in the monkey and the postmortem human brain. | the distribution of [3h]neurotensin ([3h]nt) binding sites in the monkey and the postmortem human brain was studied by using quantitative in vitro receptor autoradiography. biochemical experiments carried out on tissue sections of the monkey hippocampus showed that the binding of [3h]nt was saturable, reversible and of high specificity. the hippocampal [3h]nt binding was displaced by fragment nt 8-13 but not fragment nt 1-8 of the peptide. the anatomical analysis showed a highly heterogeneous di ... | 1987 | 3035436 |
| variable abundance of a mitochondrial dna fragment in cultured tobacco cells. | the relative abundance of a cloned 4.5 kilobase (kb) pair mitochondrial dna sequence in two suspension cultures of tobacco (nicotiana tabacum cv turkish samsun and nicotiana tabacum nt-1) has been examined. this sequence is 70-fold reduced in nt-1 relative to turkish samsun; the reduction is correlated with an increase in supercoiled mitochondrial dna. this sequence does not hybridize with mitochondrial dna from watermelon, maize, or saccharomyces cerevisiae, nor with several cloned mitochondria ... | 1987 | 3449225 |
| alterations of the composition and size of the free fatty acid pool of tetrahymena responding to low-temperature stress. | cells of tetrahymena mimbres (formerly t. pyriformis nt-1) in midlogarithmic growth under isothermal conditions (at 39 degrees c) contained a very small, compositionally discrete pool of free fatty acids, principally (60.6% of the total free fatty acid mass) palmitic and stearic acids. the composition, degree of unsaturation, and size of this free fatty acid pool were rapidly (15 min or less) altered in response to chilling. during the acclimation period following chilling to 15 degrees c, the s ... | 1987 | 3580380 |
| characterization of n-terminal fragment of proopiomelanocortin in cerebrospinal fluid. | the molecular forms of the n-terminal fragment (hnt) of proopiomelanocortin were studied in cerebrospinal fluid (csf) from normal subjects, methadone-addicted patients, patients with hydrocephalus, and a patient with nelson's syndrome. the peptides were characterized by molecular sieving and concanavalin a-sepharose chromatography. immunoreactivity was detected using antibodies directed against the n- and c-terminal portions of the hnt (hnt and gamma 3msh antibodies, respectively). the mean immu ... | 1987 | 3584397 |
| pathway of taurolipid b formation from exogenous taurolipid a by tetrahymena thermophila. | when tetrahymena thermophila was incubated with taurolipid a isolated from t. pyriformis nt-1, the exogenously added taurolipid a was deacylated rapidly, and taurolipid b content in the cells was increased. the deacylated taurolipid a (lysotaurolipid a) content reached a maximum early on during incubation, and then declined. taurolipid b and lysotaurolipid b contents in the cells were increased continuously during the incubation. these observations suggest that lysotaurolipid a was an intermedia ... | 1987 | 3620489 |
| a library of trimethylguanosine-capped small rnas in physarum polycephalum. | we have constructed a cdna library for the trimethylguanosine-capped small rnas (srnas) in the acellular slime mold physarum polycephalum. capped srnas were purified from total cellular rna of vegetative microplasmodia by preparative immunoprecipitation with anti-trimethylguanosine antibody. the purified rna was analyzed by polyacrylamide gel electrophoresis. approx. eleven different capped srnas were observed with a size range of 70-204 nucleotides (nt). based on their approximate sizes, the pr ... | 1987 | 2956157 |
| neurotensin metabolism in the rat: contribution of the kidney. | the kidney plays a key role in the metabolism of neurotensin (nt). we have examined the renal mechanisms of nt clearance by measuring plasma nt basally and after 45 min infusion of nt(1-13) in intact rats, anephric rats (no glomerular filtration, no peritubular metabolism) and ureteral ligated rats (reduced filtration). plasma nt was measured by radioimmunoassay with both c (biologically active end) and n terminal directed antisera. in anephric and ureteral ligated rats, basal plasma nt like imm ... | 1987 | 3126491 |
| dissimilar effects of l and d amino acids on the growth of tetrahymena. | of the l and d configurations of four amino acids (phenylalanine, valine, tryptophan, tyrosine) tested for influence on the growth rate of tetrahymena, only l-tyrosine was able to induce imprinting in tetrahymena pyriformis zeuthen. d-valine stimulated the division of t. pyriformis nt-1, but failed to induce imprinting. the experiments have substantiated the selectivity of the amino acid receptors of t. pyriformis, and the extraordinary imprinting potential of tyrosine as well, as judged by its ... | 1987 | 2833952 |
| protection against herpes simplex virus infection in mice by recombinant murine interferon-beta in combination with antibody. | a recombinant murine interferon -beta (rmuifn-beta) was used to suppress the development of skin lesions and death of mice after challenge with herpes simplex virus (hsv) type 1 (hsv-1). depilated female balb/c mice were inoculated intradermally with hsv-1, hayashida strain, and were administered various concentrations of interferon (ifn) intraperitoneally 3 h later. the treatment with ifn was given once a day for 10 successive days. under the conditions in which almost all control mice died aft ... | 1987 | 2821897 |
| correlation between ventilatory threshold and endurance capability in marathon runners. | the purpose of the study was to develop an index of endurance capability [i.e., "the ability to sustain a high fractional utilization of maximal oxygen uptake (vo2max) for a prolonged period of time"]. the index was based on the linear reduction of fractional utilization of vo2max with total running time greater than 7 min plotted on a log scale. the endurance index estimated from vo2max, running efficiency and the marathon performance of 18 male runners (30 +/- 7 yr old; vo2max = 66 +/- 5 ml.kg ... | 1987 | 3431378 |
| extraction of neurotensin-like immunoreactivities from porcine ileal mucosa. | the extractability of neurotensin (nt) from porcine ileal mucosa was studied by comparison of eight extraction procedures. tissue content of neurotensin-like immunoreactivity was quantitated and characterized by sequence-specific radioimmunoassays and gel filtration chromatography. homogenization prior to boiling in extraction solvent produced higher levels of the intact peptide than the reverse procedure. n-terminal immunoreactivity was not influenced by the sequence of these steps. tissue leve ... | 1987 | 3628080 |
| effect of di-n-octyl phthalate on fatty acid composition of phosphatidylcholine in tetrahymena. | we examined the effect of di-n-octyl phthalate (dop) on fatty acid composition of phosphatidylcholine (pc) in tetrahymena pyriformis nt-1. when tetrahymena cells were grown in dop-containing proteose peptone medium, the cell growth was repressed. this repression was attended by decreases in the pc content of the cells and decreases in oleic (18:1), linoleic (18:2) and linolenic (18:3) acids of pc and an increase in palmitoleic acid (16:1). the ratio of 18:1/stearic acid (18:0) of pc in cells gro ... | 1987 | 3690725 |
| direct stimulation of enzyme secretion from rat exocrine pancreas by neurotensin and its naturally occurring fragments. | neurotensin stimulates amylase release from dispersed pancreatic acini at concentrations as low as 10(-15) m. the naturally occurring fragments of neurotensin (nt), nt 1-8 and nt 1-11, also stimulate amylase secretion at concentrations that occur in peripheral plasma (10(-11) m). the analogue d-phe11 neurotensin was as potent as neurotensin itself with respect to stimulation of amylase secretion. basal plasma neurotensin levels were approximately 10 pmol/l, a concentration that stimulates the ex ... | 1987 | 2434384 |
| properties of digitonin-solubilized calmodulin-dependent guanylate cyclase from the plasma membranes of tetrahymena pyriformis nt-1 cells. | calmodulin-dependent guanylate cyclase from tetrahymena plasma membranes was solubilized in about a 22% yield by using digitonin in the presence of 0.2 mm cacl2 and 20% glycerol. the detergent, when present in the assay at concentrations above 0.05%, diminished the basal and calmodulin-stimulated activity of the enzyme. guanylate cyclase solubilized with digitonin was eluted from deae-cellulose with 200 mm kcl in a yield of 50%. properties of the solubilized enzyme were similar to those of the n ... | 1987 | 2880561 |
| e1a inducibility of the adenoviral early e2a promoter is determined by specific combinations of sequence elements. | by transient expression analysis in hela cells of adenovirus-2 e2a early (e2ae) promoter mutants and hybrid e2ae-beta-globin gene constructs, we demonstrate the existence of three nucleotide (nt) sequence elements involved in the e1a-responsiveness of the e2ae transcription unit: element i, localized within a segment (nt -13 to +62) surrounding the major e2ae cap site (nt + 1); element ii (between nt -71 and -29), and element iii (between nt -146 and -86). each element is unable by itself to con ... | 1987 | 2828188 |
| high affinity binding of [3h]neurotensin of rat uterus. | [3h]neurotensin (nt) was found to bind specifically and with high affinity to crude membranes prepared from rat uterus. scatchard analysis of saturation binding studies indicated that [3h]nt apparently binds to two sites (high affinity kd 0.5 nm; low affinity kd 9 nm) with the density of high affinity sites (41 fmoles/mg prot.) being about one-third that of the low affinity sites (100 fmoles/mg prot.). in competition studies, nt and various fragments inhibited [3h]nt binding with the following p ... | 1987 | 2831520 |
| the neurotensin analog xenopsin excites nigral dopamine neurons. | the electrophysiological effects of neurotensin (nt), its analog xenopsin, and the fragment nt-(1-8) on the activity of dopaminergic neurons in rat substantia nigra slices were compared. xenopsin and nt produced a concentration-dependent increase in the firing rate. the mean firing rate was increased by 58.5% with xenopsin (0.1 microm) and 49.1% with nt (0.1 microm). nt-(1-8) was inactive at this concentration. dopamine (100 microm) inhibited firing in these neurons by 54.7%. these data provide ... | 1988 | 3350051 |
| survey of distribution of substance p, vasoactive intestinal polypeptide, cholecystokinin, neurotensin, met-enkephalin, bombesin and phi in the spinal cord of cat, dog, sloth and monkey. | levels of substance p (sp), peptide-histidine-isoleucine (phi), vasoactive intestinal polypeptide (vip), cholecystokinin (cck), neurotensin (nt), bombesin (bom) and methionine-enkephalin (met-enk) like immunoreactivity were measured in cat, dog, primate and sloth cervical, thoracic, lumbar and sacral dorsal and ventral horns and dorsal root ganglia. the levels of peptides in the cat sacral cord and the principal peaks of immunoreactivity on a 10-60% acetonitrile gradient on a c18 reverse phase h ... | 1988 | 2453858 |
| a family of non-allelic trna(valguu) genes from the cellular slime mold dictyostelium discoideum. | a haploid genome of the cellular slime mold dictyostelium discoideum contains at least 14 non-allelic gene copies coding for a trna(valguu). the structure, genomic organization, and expression of these genes have been analyzed in relation to stages of the developmental cycle. so far, 13 trna(valguu) genes have been isolated and characterized. all genes contain identical mature trna-coding regions, and consequently identical gene internal promoter elements. however, different genes differ with re ... | 1988 | 3072263 |
| isolation and structural characterization of a diacyltaurolipid in cells of tetrahymena mimbres. | a diacyltaurolipid was found in cells of tetrahymena mimbres (formerly tetrahymenas pyriformis nt-1). the lipid accounted for about 0.05% of the total lipids of the cells, and was composed of taurine (1 equiv.), 3,7,13-trihydroxystearic acid (1 equiv.) and non-hydroxy fatty acids (2 equiv.). by mild alkaline hydrolysis, non-hydroxy fatty acids (2 equiv.) and 2-(3,7,13-trihydroxyoctadecanoyl)aminoethanesulfonic acid were obtained. for determination of the positions of the ester bonds of the lipid ... | 1988 | 3132980 |
| in vivo inactivation of neurotensin in dog ileum: major involvement of endopeptidase 24-11. | the metabolism of tritiated neurotensin (nt) after close i.a. perfusion in ileal segments of anesthetized dog was studied. venous effluents containing labeled metabolites and intact nt were collected and analyzed by high-performance liquid chromatography. the apparent half-life of the peptide was between 2 and 6 min. the tritiated metabolites of nt were identified as free tyrosine, nt-(1-7), nt-(1-8), nt-(1-10), nt-(11-13) and nt-(1-11). pretreatment of dog ileum with thiorphan or captopril indi ... | 1988 | 2855236 |
| detection of a new hybrid alpha 2 globin gene among american blacks. | we have examined the alpha globin gene complex for 49 individuals with alpha-thalassemia-2 (-alpha 3.7). crossovers resulting in alpha-thalassemia-2 (type i) were observed in all 57 chromosomes with the -alpha 3.7 defect. except for one alpha-thalassemia-2 chromosome, all were linked to the absence of an rsa i restriction site located 0.7 kb 5' to the alpha 2-globin gene; this polymorphic site was observed for 10 of 38 non-alpha-thalassemia chromosomes from black americans. in four black familie ... | 1988 | 2896623 |
| the dynamics of arachidonic acid liberation and prolactin release: a comparison of thyrotropin-releasing hormone, angiotensin ii, and neurotensin stimulation in perifused rat anterior pituitary cells. | the dynamics of arachidonic acid (aa) liberation and prl release were highly correlated in perifused rat anterior pituitary cells during stimulation by three different neuropeptides: trh, angiotensin ii (aii), and neurotensin (nt). after preincubation of these cells with 1 microci [3h]aa, a 20-min perifusion with aii (100 nm), trh (100 nm), or nt (1 microm) elicited a sharp initial increase in prl release and [3h]aa efflux, which rapidly subsided (within 6 min) to less elevated levels of prl rel ... | 1988 | 3139397 |