FMRFamide-like peptides in the locust: distribution, partial characterization and bioactivity

1990 ◽  
Vol 149 (1) ◽  
pp. 335-360 ◽  
Author(s):  
S. Robb ◽  
P. D. Evans
Keyword(s):  
High Pressure ◽  
Nervous System ◽  
Liquid Chromatography ◽  
Nervous Tissue ◽  
Schistocerca Gregaria ◽  
Quantitative Distribution ◽  
Putative Target ◽  
Target Sites ◽  
Neuromuscular Preparation ◽  
Different Parts

The quantitative distribution of FMRFamide-like peptides in the nervous system and in their putative target sites in the locust Schistocerca gregaria is described using radioimmunoassay techniques. The nature of the immunoreactive material has been characterized by high-pressure liquid chromatography. At least six peaks of FMRFamide-like immunoreactivity can be separated in extracts of locust nervous tissue. The relative proportions of these peaks vary from tissue to tissue, suggesting a differential expression of FMRFamide-like peptides in different parts of the locust nervous system. The bioactivity of the endogenous FMRFamide-like peptides has been assessed on the extensor tibiae neuromuscular preparation and on the locust heart. The results suggest that FMRFamide-like peptides in the locust function both as circulating neurohormones and as locally released neuromodulators or neurotransmitters.

Characterization of placental luteinizing hormone-relasing factor-like material

1981 ◽  
Vol 96 (3) ◽  
pp. 394-397 ◽  
Author(s):  
Jau-Nan Lee ◽  
Markku Seppälä ◽  
Tim Chard
Keyword(s):  
Central Nervous System ◽  
High Pressure ◽  
Nervous System ◽  
Acetic Acid ◽  
Liquid Chromatography ◽  
Luteinizing Hormone ◽  
Human Placenta ◽  
The Central Nervous System ◽  
Inhibition Curve

Abstract. High pressure liquid chromatography (HPLC) and radioimmunoassay were employed to characterize luteinizing hormone-releasing factor (LRF)-like material in the human placenta. Methanol extracts of the placenta were washed with acetic acid and chloroform, further purified on coarse octadecylsilane columns, fractionated on HPLC, and tested by radioimmunoassay. In HPLC, placental LRF had the same retention time as synthetic LRF, and such fractions gave an inhibition curve which was parallel to that of synthetic LRF in radioimmunoassav. It is concluded that human placental I.RF is similar or identical to LRF in the central nervous system.

Quantitative Distribution of Lichen Products in Australian Scyphose Cladonia Species

1981 ◽  
Vol 13 (3) ◽  
pp. 259-263 ◽  
Author(s):  
A. W. Archer
Keyword(s):  
High Pressure ◽  
Liquid Chromatography ◽  
High Pressure Liquid Chromatography ◽  
Capillary Flow ◽  
Internal Standard ◽  
Reverse Phase ◽  
Quantitative Distribution ◽  
Saturated Solutions

AbstractThe quantitative distribution of five lichen acids, including fumarprotocetraric acid, in seven specimens of Australian scyphose Cladonia species was determined by reverse phase high pressure liquid chromatography, using butylated hydroxy-toluene as internal standard. The highest concentrations of lichen acids were found in the scyphi and it is suggested that this localized distribution of lichen acids is due to repeated upward capillary flow, of saturated solutions of the acids, in the podetia followed by evaporation in the upper parts of the podetia.

Postnatal Development of Circadian Rhythm in Serum Cortisol Levels in Children

PEDIATRICS ◽  
1983 ◽  
Vol 72 (3) ◽  
pp. 399-404 ◽  
Author(s):  
Shoju Onishi ◽  
Genji Miyazawa ◽  
Yutaka Nishimura ◽  
Satoru Sugiyama ◽  
Takeshi Yamakawa ◽  
...  
Keyword(s):  
Central Nervous System ◽  
High Pressure ◽  
Nervous System ◽  
Circadian Rhythm ◽  
Liquid Chromatography ◽  
Congenital Anomalies ◽  
Serum Cortisol ◽  
Endocrine Diseases ◽  
The Central Nervous System

High-pressure liquid chromatography was used to study the development of blood adrenocortical circadian rhythm in a total of 64 children, ranging in age from 1 month to 15 years. Patients with endocrine diseases, congenital anomalies, and diseases of the central nervous system were excluded from this study. Determination of corticosteroid concentration was possible with 20 to 100 µL of serum. Twenty-four hour patterns were determined at six-hour intervals. A distinct circadian rhythm with an amplitude comparable to that of an adult emerged at approximately 6 months of age.

Preparation and properties of three analogues of [5-leucine]enkephalin, substrates for enzyme conversion studies

1985 ◽  
Vol 50 (6) ◽  
pp. 1329-1334
Author(s):  
Jaroslav Vičar ◽  
Linda Servítová ◽  
Martin Flegel ◽  
Karel Hauzer ◽  
Tomislav Barth
Keyword(s):  
High Pressure ◽  
Liquid Chromatography ◽  
Guinea Pig ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Guinea Pig Ileum ◽  
Opioid Activity ◽  
C Terminus ◽  
N Terminus ◽  
Fragment Condensation

Analogues of [5-Leu]enkephalin, prolonged by methionine on the N-terminus or, by lysine or methionine on the C-terminus were prepared by fragment condensation, purified by ion exchange chromatography or high-pressure liquid chromatography. The substances were characterised by their opioid activity in a test on guinea-pig ileum in comparison with the activity of [5-Leu]enkephalin.

Production of Aflatoxin in Cocoa Beans

1979 ◽  
Vol 62 (5) ◽  
pp. 1076-1079 ◽  
Author(s):  
Lawrence M Lenovich ◽  
W Jeffrey Hurst
Keyword(s):  
High Pressure ◽  
Liquid Chromatography ◽  
Ivory Coast ◽  
Aspergillus Parasiticus ◽  
Aflatoxin Production ◽  
Growth Conditions ◽  
Aflatoxin Contamination ◽  
Cocoa Beans ◽  
Total Aflatoxin ◽  
Substrate Variation

Abstract Aflatoxin was produced in both non-autoclaved and autoclaved Ivory Coast cocoa beans inoculated with Aspergillus parasiticus NRRL 2999 under optimum laboratory growth conditions. Total aflatoxin levels ranged from 213 to 5597 ng/g substrate. Aflatoxin was quantitated by using high pressure liquid chromatography (HPLC). Raw, non-autoclaved cocoa beans, also inoculated with aspergilli, produced 6359 ng aflatoxin/g substrate. Variation in aflatoxin production between bean varieties was observed. Total aflatoxin levels of 10,446 and 23,076 ng/g substrate were obtained on Ivory Coast beans inoculated with A. parasiticus NRRL 2999 and NRRL 3240, respectively. Aflatoxin production on Trinidad and Malaysian beans was 28 and 65 ng aflatoxin/g substrate. These data support previously reported low level natural aflatoxin contamination in cocoa.

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