Biomedical subjects

I Neeman

Publications and source records attributed to I Neeman.

28 records · Page 2Linked to original sources

PubMed1989

The effect of avocado oils on some liver characteristics in growing rats.

The effects of various avocado oils on some liver characteristics were studied in growing rats. The rats were fed diets containing 10% (w/w) avocado oil for 4 wk. In comparison with rats fed refined oil obtained from cored fruit by centrifugal separation, rats fed unrefined avocado oil obtained by solvent extraction from the intact fruit, or refined avocado oil containing avocado-seed oil, showed significant growth inhibition, an increase in the amount of hepatic lipids (identified as steatosis by histopathological examination), and a decrease in levels of triglycerides in blood. Rats fed the refined oil containing unsaponifiable material prepared from unrefined oil from the intact fruit showed similar responses. Fatty livers were not induced by feeding rats unrefined avocado oil obtained from intact fruit by centrifugal separation, although a significant decrease in blood triglycerides was observed. There were no significant differences between groups in serum total protein, albumin or bilirubin content or in alanine aminotransferase activity. However, serum alkaline phosphatase activity was increased in rats fed the seed oil, the unrefined solvent-extracted oil from intact fruit, or the unsaponifiables, and aspartate aminotransferase activity was significantly increased in the group fed avocado-seed oil. These data suggest that consumption of avocado oil extracted from intact fruit may cause changes in liver metabolism.

Animal Feed↗

PubMed1985

Induced chemiluminescence of oxidized fatty acids and oils.

The injection of a strong organic base into milligram quantities of fats and oils dissolved in methylene chloride results in a burst of chemiluminescence whose peak intensity is a function of the previous thermal oxidation history and of the degree of unsaturation of the starting material. The flash of this induced chemiluminescence can be 10(8) times higher than the steady-state "spontaneous" chemiluminescence. The kinetics of the induced chemiluminescence are first order in concentration and second order in time. The emission spectrum is broad and extends into the near infrared. A model based on dioxetane chemiluminescence is proposed to explain the observed kinetics.

Fatty Acids↗

PubMed1984

Ghost cells as sorption matrix for virus concentration from water.

Pig erythrocyte membranes were used as adsorbent material for the concentration of bacteriophage phi x-174, MS-2, and f2 from 5 ml of saline solution. The adsorption was carried out at pH 3.5, and the elution was carried out at pH 7.0. Compared with adsorption on 3% beef extract, bacteriophage adsorption on erythrocyte ghost cells yielded 93 to 100%, and elution was 92 to 100%, whereas beef extract organic flocculation yielded adsorption of 0 to 98.8% and elution of 61 to 86.6%. The same procedure but with poliovirus LSC-1 gave 100% adsorption and 91 to 129% elution.

Adsorption↗

PubMed1983

2 Methylene-beta-alanine methyl ester: a toxic amino acid originating from the sponge Fasciospongia cavernosa.

N-acyl-2-methylene-beta-alanine methyl esters (A) are the main lipidic compounds in the sponge Fasciospongia cavernosa. These compounds were isolated and after methanolysis--2 methylene-beta-alanine methyl esters (AA) and free fatty acid methyl esters were obtained. The interaction of A and AA with the thiol group of cysteine was detected by Ellman's procedure. Both A and AA interact with the thiol group of cysteine in the pH range of 6.0-8.0. Both compounds were found to be strong inhibitors of glyceraldehyde triphosphate dehydrogenase (TPD) from rabbit muscle. The inhibitory effect of A and AA decreases upon addition of beef extract and other protein mixtures containing thiol groups. E. coli growth on a synthetic medium was inhibited by compound AA. Resistant E. coli varieties were isolated by techniques of enrichment cultures. Some of these resistant varieties were shown, by cross-feeding with cysteine dependent E. coli varieties, to excrete cysteine and cysteine derivatives.

Alanine↗

PubMed1983

A novel micromethod for the Limulus amebocyte lysate (LAL) assay for endotoxin, based on hydrostatic pressure.

A micromethod for performing the Limulus amebocyte lysate (LAL) assay for the presence of endotoxin is described which requires only about five percent of the standard amount of LAL reagent. The method is based upon measuring an increased amount of hydrostatic pressure required to cause a gelled LAL sample to flow from a capillary tube. The method is simple, rapid and correlates well with the results of the standard LAL assay procedure.

Animals↗

PubMed1983

Partial isolation and characterisation of a hemagglutinating factor from avocado seed.

Extracts of ground avocado seeds (Fuerte and Hass varieties), prepared in different buffer solutions (pH 2.0-12.0), show hemagglutinating activity towards A, B, AB, and H (0) human erythrocytes. The extract showing the highest titer of aggulination was extracted at pH 10.5. The crude extract also causes hemolysis of fresh washed erythrocytes. The hemagglutinating factor is not inhibited by most of the simple sugars tested, e.g., D-glucose, D-mannose, D-galactose, and glucose-amine. The only sugars which show some inhibitory effect are N-Acetyl-neuraminic acid, melibiose, and stachiose. Basic amino acids, e.g., lysine and arginine also inhibit its activity. However the most potent inhibitors of the agglutinin are proteins and glycoproteins such as bovine serum albumin, collagen, thyroglobulin, ovalbumin, mucin, and fetuin. The agglutinin is adsorbed on polymer beads such as Sepharose 4B, Sephadex G100, Agarose, and Chitin, and it reacts with hog erythrocyte membranes. It can be partially eluted from those materials with alkaline buffers (pH 9.0-10.5).

Animals↗

PubMed1981