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Determination of the fatty acid and triglyceride compositions of the F,(Elaeis guineensis X E. oleifera), F2and the backcross hybrid mesocarp oils demonstrated that most fatty acid and triglyceride compositions of oils from hybrid palms are intermediate between those of their respective parentals. These data, as well as the acyl group (saturated/palmitate and unsaturated/oleate) distribution of triglycerides of the F2mesocarp oils provide genetic proof for codominance in the F2generation which shows a characteristic segregation into the co-dominance ratio of 1:2:1 (i.e., 1 E.guineensis: 2 F1hybrid: 1E. oleifera). Similar analyses into the backcross hybrid mesocarp oils on the whole confirmed co-dominance when the backcross ratio of 1:1 was obtained. These results are used to develop the Co-Dominance Theory ofElaeispalm hybridization which makes successful predictions for mesocarp oils from the different hybrid palms.

Dipeptidyl peptidase II (Dpp II) was demonstrated histochemically in soleus, extensor digitorum longus, cardiac, and vascular smooth muscle tissues using Lys-Ala-4-methoxy-beta-naphthylamide or Lys-Pro-4-methoxy-beta-naphthylamide as the substrate. The enzyme was found to be localized in discrete granules in all muscle types, but varied in its apparent activity. Dpp II activity was greatest in cardiac and least in extensor digitorum longus muscles with activity in soleus and vascular smooth muscles in between these extremes. Since Dpp II is localized only in lysosomes, the relative amounts and locales of lysosomes can be easily observed in normal muscle cells by the techniques described in this study.

A case of severe schizophrenia is described in a patient with chromosomal mosaicism of Klinefelter's syndrome (XXY) and trisomy 8. The literature of both syndromes is reviewed and the aetiological implications discussed.

Histochemical demonstration of cathepsin B activity was performed for the soleus, extensor digitorum longus, cardiac and vascular smooth muscle tissues of the rat using CBZ-Arg-Arg-4-methoxy-beta-naphthylamide or CBZ-Ala-Arg-Arg-4-methoxy-beta-naphthylamide as the substrate. The enzyme varied in its apparent activity but was localized in discrete granules in all muscle types. Cathepsin B was most active in cardiac muscle and least active in extensor digitorum longus muscles in between these extremes similar to another lysosomal protease, dipeptidyl peptidase II. However, in both types of skeletal muscle, the granules were observed more frequently at the periphery of the muscle cell just beneath the sarcolemma. Since cathepsin B is found only in lysosomes, this subsarcolemmal predominence may indicate that only one population of lysosomes in muscle contains active cathepsin B. All cathepsin B activity was abolished in the presence of the protease inhibitor, leupeptin.

The growth factor receptor-binding protein (Grb2) has a key role in initiating the mitogen-activated protein kinase signaling cascade in major cell regulatory pathways. The binding of proteins to the SH2 domain of Grb2 has been reported to occur mainly after they are tyrosine-phosphorylated following receptor activation. Using an in vitro binding assay, immunoprecipitation, and Far Western techniques, we report that in quiescent cells a 75-kDa protein binds directly to the SH2 domain of Grb2. All of the tyrosine-phosphorylated p75 protein co-localizes with Grb2.Sos complex in the cytosolic fraction of the cell in vivo and undergoes tyrosine dephosphorylation when cells are treated with mitogenic ligands such as epidermal, platelet-derived, and fibroblast growth factors, endothelin-1, and bombesin but not tumor necrosis factor-alpha, interferon-alpha and -gamma, interleukein-6, and leukemic inhibitory factor, which are either cell growth inhibitory or not significantly mitogenic. The dephosphorylation of p75 and the ensuing dissociation from Grb2 is rapid, occurring within 30 s following mitogenic stimulation by ligands such as epidermal growth factor, suggesting p75 to be an early component in the signal transduction pathways involving Grb2.

Tyrosine phosphorylation of cellular proteins occurs rapidly upon treatment of fibroblasts with acidic or basic fibroblast growth factors (aFGF, bFGF), suggesting a role for protein phosphorylation in the FGF signaling pathway. Stimulation of Swiss 3T3 cells and MRC-5 fibroblasts with bFGF results in the tyrosine phosphorylation of several proteins, of which the most prominent has been designated as p90. The phosphorylation of p90 is observed within 30 s of treating the cells with FGF but not with other growth factors. Microsequencing of p90 resolved on two-dimensional polyacrylamide gel electrophoresis indicated an N-terminal amino acid sequence which corresponded to a protein previously named as 80K-H. Polyclonal antibodies raised against the predicted C terminus of 80K-H recognized p90 on all Western blots. p90 was found to bind specifically to GRB-2-glutathione S-transferase fusion protein and to be immunoreactive with 80K-H antibody. In addition, anti-phosphotyrosine antibodies immunoprecipitated 80K-H from cell lysates of FGF-stimulated but not from control fibroblasts. The biological function of 80K-H is yet unknown. However, from this study and a previous observation of the obligatory dependence of p90 phosphorylation on FGF receptor occupation, it appears that 80K-H is involved in FGF signaling.

In immunohistochemical studies of rat liver tissue slices and purified nuclei, adenosine 3':5'-cyclic monophosphate (cAMP) and guanosine 3':5'-cyclic monophosphate (cGMP) immunofluorescence on the nuclear membrane are sequentially increased after glucagon administration. An explanation for the increased cGMP immunofluorescence was sought in experiments in which guanylate cyclase [GTP pyrophosphate-lyase (cyclizing), EC 4.6.1.2]activity of hepatic subcellular fractions was determined. The results showed that a nuclear guanylate cyclase exists which can be distinguished from the soluble and crude particulate guanylate cyclases. The activity of the nuclear enzyme was increased by 35% in nuclei isolated from rats 30 min after glucagon injection, the time at which maximal nuclear membrane cGMP immunofluorescence is observed. Because glucagon altered both cAMP location and levels prior to the observed changes in nuclear cGMP metabolism, the hypothesis that cAMP acted as the second messenger was tested. In vitro incubation of nuclei isolated from control rats with 10(-5) M cAMP produced a 25% increase in nuclear guanylate cyclase activity. With nuclei isolated from glucagon-treated rats, no significant increase in enzyme activity was observed; this indicates that maximal stimulation of nuclear guanylate cyclase by cAMP occurred at levels that are obtained in vivo after glucagon administration. These findings suggest that hepatic nuclear cGMP content may be regulated by a specific organelle guanylate cyclase and that cAMP may be one of the determinants of this enzyme's activity.

Cyclic GMP and cyclic AMP have been localized in rat liver, small intestine, and testis by a fluorescent immunocytochemical procedure. In liver, cyclic AMP is distributed along sinusoids predominantly, and increased fluorescence is seen sinusoidal areas after glucagon administration. Cyclic GMP is located in nuclear elements and on the plasma membranes of hepatocytes. In jejunum, cyclic AMP is found predominantly at the basal and lateral sides of brush border cells and in the lamina propria, while cyclic GMP is located to the brush border membrane, smooth muscle, and nuclear elements. In testis, cyclic AMP is found in cytoplasm of cells at the perimeter of the seminiferrous tubules and in interstitial cells, while cyclic AMP is visualized on the plasma membrane of the cells lining the tubules. Cyclic GMP is also seen on chromosomes of premeiotic spermatocytes and in sperm. These data provide histological evidence implicating diverse roles for the nucleotides in these tissues. The nuclear localization of cyclic GMP in all of these tissues suggests a role for the nucleotide in nucleus-directed events.

An algorithm for the detection and measurement of the glomerular basement membrane in kidney electron micrographs by image analysis techniques is described. Starting from a user-specified point, local features within a small window are computed to give a feature score. Feature scores for adjacent neighbourhoods are also determined, and windows that satisfy similarity criteria are linked to produce the centerline of the membrane. A region-growing process completes the segmentation procedure. The adaptive and local nature of the algorithm ensures successful segmentation despite the complex and variable characteristics of the micrograph image.

This paper considers the evaluation of the distribution functions of the bivariate gamma distribution of Wicksell and Kibble, and a bivariate inverted beta distribution. Simple expansions of the distribution functions in terms of marginal quantities and the negative binomial probabilities are derived.

One of the most obvious changes when oils are heated is color darkening. Palm oil darkens very rapidly compared to other oils. The cause of this rapid color development was investigated. Various methods used to pretreat Lotox crude palm oil (CPO) to retard darkening during heating were by agitation with activated carbon S511, by water and water/isopropyl alcohol (95:5) washing of neutralized and unneutralized oil, and by liquid/liquid extraction of oil using water and water/isopropyl (95:5). Pretreatment of CPO did succeed in retarding color development. Retardation was especially evident in oils previously neutralized with sodium hydroxide before washing with water and water/isopropyl alcohol. The UV spectra of the liquid/liquid extracts showed strong absorption maxima at 256 nm. The addition of a base resulted in darkening of the extracts accompanied by shifts to longer wavelengths (288 nm). Reaction with freshly diluted 1–2% ferric chloride solution gave a brown color. The development of paper chromatography in butanol: acetic acid:water (6:1:2) revealed a blue fluorescence near the solvent front, with the same relative retention time as that of tannic acid. This evidence indicates that phenolic compounds were responsible for color darkening in palm oil.