Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The simultaneous purification and concentration of synthetic human beta-endorphin from plasma is described, which when used together with an appropriate isocratic high-performance liquid chromatographic-electrochemical detection (HPLC-ED) system allows the determination of elevated physiological levels of beta-endorphin. Purification of plasma was gained by flash-freezing in liquid nitrogen, acidifying with 100 microliters of trifluoroacetic acid (10%, v/v) per ml of plasma, thawing at 4 degrees C and centrifuging to remove any precipitate. Solid-phase extraction with silica sorbent was utilised, which allowed further isolation of the analyte, a method of concentration and a procedure whereby beta-endorphin could be transferred to the HPLC mobile phase. Silica sorbent demonstrated greater selectivity than C18 for synthetic human beta-endorphin and, in addition, provided improved recovery of this analyte when utilising elution volumes of 500 microliters or less. Proteolytic degradation and heparin-induced high-affinity binding in plasma were shown not to effect the recovery of beta-endorphin if blood was rapidly chilled and plasma quickly obtained, frozen and acidified. Validation of this purification/concentration method using [125I]beta-endorphin demonstrated a recovery of 85.6% which was not jeopardised when concentrating the sample twenty-fold. This provided an increase in the sensitivity of detection, when used in conjunction with HPLC-ED, from 5 ng/ml to 250 pg/ml.
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PMID:Measurement of beta-endorphin in human plasma by high-performance liquid chromatography with electrochemical detection: validation of a method employing the simultaneous purification and concentration of beta-endorphin. 138 50

Silica-based ion-exchange Sep-Pak cartridges, packed with either carboxymethyl (CM) cation-exchanger or a quaternary methyl ammonium (QMA) anion exchanger, are now available. The feasibility of using ion-exchange Sep-Pak cartridges for the fractionation of pituitary peptides was investigated. Extracts of bovine posterior pituitaries were fractionated at either pH 5 or pH 7 by pairs of cation and anion exchangers, connected in series. The capacity to bind peptides was well correlated with the theoretical charge calculated for a variety of peptides. At pH 5 the entire tissue extract could be fractionated into either basic or acidic pools. In contrast, at pH 7 only the more basic or acidic peptides were retained by the respective ion exchangers. The rest of the peptides passed through both ion exchangers and were recovered in the neutral pool. The ion-exchange fractionation principle was used to facilitate the purification of 35S-labelled intermediate pituitary glycopeptides, prepared by incubating mouse intermediate lobes in explant culture with 35S-labelled sulphate. 35S-labelled glycosylated forms of Lys1 gamma 3MSH, corticotropin-like intermediate lobe peptide, and the amino terminal or 16K fragment of pro-opiomelanocortin (i.e. 16K1-74) were fractionated into separate pools such that they could be purified to homogeneity in a single step by reversed-phase high-performance liquid chromatography (RP-HPLC). Purification by conventional means would require at least two RP-HPLC steps. Thus, radiolabelled peptides can be purified with the minimum of chromatographic manipulation, thereby ensuring maximal recoveries.
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PMID:Use of ion-exchange Sep-Pak cartridges in the batch fractionation of pituitary peptides. 373 37

Experiments on the CBA mice that had been within 30 km of the Chernobyl NPP accident for 3 months revealed a decrease in the phagocytic and bactericidal properties of peritoneal macrophages accompanied with a disturbance in the production of interleukin-1 and a tumor necrosis factor responsible for the cell immunity. A single administration of a silicon-containing enterosorbent Aerosil-350 expedient to remove radionuclides and ensure the organism detoxication made it possible to correct and restore the affected cell and organism immunity for 7 days.
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PMID:[The immunocorrection with Aerosil-350 of the natural resistance of mice found under conditions of an elevated radiation background]. 918 66

The protective effect of co-administration of recombinant mouse granulocyte-macrophage colony-stimulating factor (rmGM-CSF) and synthetic peptide met-enkephalin (M-ENK) against blood-induced Plasmodium berghei infection in Swiss mice was investigated. Mice co-administered with rmGM-CSF (10.0 mug/kg) and M-ENK (2.0 mg/kg) x 3/day, i.p., beginning on day -1 and continuing through day +4 after the initiation of infection, showed significant suppression (p < 0.05) (sometimes even complete elimination) of parasitaemia compared to vehicle-treated controls. However, when administered separately, neither of these agents induced any detectable protective effect. Surprisingly, mice similarly co-administered with rmGM-CSF (10.0 mug/kg) and higher doses of M-ENK (10.0 mg/kg), showed no protection. Polyclonal neutralizing (100%) antibody to rmGM-CSF abrogated the combined protective effect of these agents. Additionally, naloxone (10.0 mg/kg/day x 6, i.p.), a non-selective, opioid receptor antagonist, also blocked the combined protection. Mice that survived the challenge showed a significant increase (p < 0.05) in total circulating leukocytes counts, and the pool-size and the phagocytic activity of both the peritoneal and splenic macrophages, ex vivo. Silica (3.0 mg/mouse, i.v.) abrogated the combined protective effect of rmGM-CSF and M-ENK. These results indicate that co-administration of rmGM-CSF and dose dependent quantities of M-ENK in P. berghei-infected mice can protect against malaria, apparently through macrophage-mediated mechanisms.
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PMID:Protection of mice from malaria after co-administration of recombinant mouse granulocyte-macrophage colony- stimulating factor and methionine-enkephalin. 1156 34