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Notes: Abstract: Ependymins are thought to be implicated in fundamental processes involved in plasticity of the goldfish CNS. Gas-phase sequencing of purified ependymins β and γ revealed that they share the same N-terminal sequence. Each sequence displays microheterogeneities at several positions. Based on the protein sequences obtained, we constructed synthetic oligonucleotides and used them as hybridization probes for screening cDNA libraries of goldfish brain. In this article we describe the full-length sequence of a mRNA encoding a precursor of ependymins. A cleavable signal sequence characteristic of secretory proteins is located at the N-terminal end, followed directly by the ependymin sequence. Also, two potential N-glycosylation sites were detected. A computer search revealed that ependymins form a novel family of unique proteins.

Notes: The corrections to the equilibrium rate of the chemical reaction A+B→products are analyzed for the Lorentz gas composed of light particles A reacting with heavy particles B in the presence of heavy particles of a carrier gas C. Particles B and C are treated as a heat bath. The reaction is analyzed under conditions in which the products can be neglected. The model of reacting hard spheres (line-of-centers model) introduced by Present is used. Analysis is performed in two ways: (1) By obtaining analytical expressions following from the Chapman–Enskog perturbation solution of the Boltzmann equation generalized for gases reacting chemically. (2) By obtaining numerical results which follow from a numerical solution of a partial differential equation which can be derived from the Boltzmann equation for the reactive Lorentz gas. It is shown that for a specified region of system parameters both types of solution of the Boltzmann equation coincide. The comparison of both methods permits us to find out under which conditions the perturbation method of solution may be used.

Notes: Calcium salts of high-oleic sunflower oil (〉 86% oleic acid) were prepared and fed at 0% and 7.5% of diet dry matter weight to 8 Holstein cows in early- to mid-lactation in a cross-over experimental design. Oleic acid content of milk fat increased from 26% to over 40% and cholesterol-raising saturates were reduced from 41% to 33%. Latin American white cheese, queso blanco, was produced from modified and normal milk. No differences in firmness were found between cheeses using penetration-compression testing with an Instron machine. Sensory difference tests indicated no significant differences between cheeses. Latin American white cheeses made with high oleic milk are similar to traditional cheese.

Notes: Patients with renal disease often develop accelerated atherosclerosis resulting in more frequent cardiovascular complications compared to the general population. It has been suggested that peroxidation of low density lipoprotein (LDL) contributes to the pathogenesis of atherosclerosis and glomerulosclerosis. The present study aimed to investigate the phosphatidylcholine hydroperoxide (PC-OOH) content of LDL in patients with chronic renal failure (CRF) and patients on haemodialysis (HD). Plasma was obtained from healthy volunteers (n = 20; age 45.8 ± 16.9 years), CRF patients (n = 23; age 49.4 ± 18.1 years) and patients on HD (n = 19; age 59.1 ± 10.3 years). The lipid profile was studied in all patients. The LDL was isolated by sequential ultracentrifugation. The oxidized PC-OOH content of LDL was measured by high performance liquid chromatography with chemiluminescence detection (HPLC-CL). Compared to the controls, patients with proteinuria had significantly higher plasma concentrations for total cholesterol, LDL-cholesterol and apoB, whereas patients on HD had significantly higher levels of triglycerides and reduced HDL and apoA1 plasma concentrations. Significantly elevated levels of PC-OOH were found in HD patients (22.56 ± 13.40 pmol/mg LDL-cholesterol) and CRF patients (13.12 ± 15.15 pmol/mg LDL-cholesterol) compared to the controls (0.56 ± 0.38 pmol/mg LDL-cholesterol; P 〈 0.001). In HD patients the PC-OOH concentration was higher compared to CRF patients (P 〈 0.05). It was concluded that lipid hydroperoxides increase in renal disease and in patients on HD. These elevated lipid hydroperoxides may contribute to the increased risk for atherosclerosis in these patients.

Notes: Dispersibility of soy protein isolates was improved by adjusting pH to 12 and acidifying to pH 6.5. Alkaline treated isolates added to reconstituted nonfat milk reduced rennet induced coagulum firmness and syneresis more than did untreated soy protein isolates. Treated soy protein added to reconstituted nonfat dry milk reduced coagulum firmness and syneresis more than untreated soy protein. Soy protein interference with coagulum firmness and syneresis increased with an increase in pH becoming most severe at pH values above 11. Adjusting the pH of reconstituted NFDM in the absence of soy protein to pH 8 and holding for 30 min before adjusting it back to pH 6.5 had no effect on coagulum firmness or syneresis. However, higher pH treatments (pH 10 and above) caused reduction in coagulum firmness and in syneresis.

Notes: Summary This manuscript reviews recent studies on the characterization of functional surface antigens on human NK cells. A series of cloned NK cell lines has been utilized for examination of these structures. These clones provide a relatively large number of cells with a stable phenotype and consistent specific cytotoxicity, which reflect the diversity of uncultured NK cells in normal peripheral blood. Almost all clones express the T11 antigen, some have a mature T-cell phenotype (T3+, T11+), and only one (JT1) does not reveal any T-cell antigen at all (T3−, T11+). Using NK clones to generate monoclonal antibodies specific for NK-associated antigens, two structures have been identified, NKH1 and NKH2. NKH1 appears to be exclusively expressed on large granular lymphocytes (LGL) of peripheral blood and was found to be a pan-NK cell antigen. NKH2 is also expressed primarily by LGL, but NKH2-positive LGL do not display a high level of NK activity. Another surface structure that has been found to play an important role in NK cell function is the T11 antigen/E rosette receptor complex, which is expressed in 80% of peripheral blood NK cells. The T11 antigen complex has been described as possessing the T111, T112, and T113 antigens and is an important alternate pathway for antigen-independent T-cell activation. Using anti-T112 and anti-T113 monoclonal antibodies, IL-2 receptor expression could be induced on various NK clones if they expressed the correct T11 antigenic epitope. As anti-T112/3 antibodies had a direct proliferative effect on NK cells with mature T-cell phenotype (T3+), it is proposed that the production of IL-2 by NK clones is largely dependent on the T-cell phenotype of NK cells. All NK clones expressed IL-2 receptor at low density and therefore needed a ten fold higher concentration for maximal proliferation than T-cell clones. For some T-cell-like NK clones, the T3 antigen complex and a T-cell receptor-like structure, NKTa or NKTb, have been shown to define the target cell specificity. The activation antigen, TNKTAR, was characterized as the recognition structure on the target cell for these NK cells. For both T3− and T3+ NK clones, the LFA-1 antigen has been shown to play an important role in effector/target cell interaction. As previously described for CTL, the LFA-1 molecule is involved in NK cytotoxicity as a nonspecific adhesion-strengthening molecule at the effector cell level. In summary, NK cells have been found to have a number of unique surface antigens such as NKH1 and NKH2, which can be used to identify and characterize NK cells in vivo. In addition, analysis of surface antigens on NK cells has identified a number of functional structures, such as T11, T3, NKTa and LFA-1, which are shared by T-cells and which function in a fashion similar to both types of cells. Taken together, this analysis therefore indicates that NK cells have a strong functional relationship with T-cells and supports the conclusion that these cells are derived from the T-cell lineage.