Determination of antibody affinity by using antigenic and antibody immunosorbents

To determine the affinity of the active centers of antibodies, cellulose immunosorbents for antibodies and antigens have been used. The fixation of serum proteins on the sorbent, the interaction of fixed antibodies with a monovalent antigen and the graphic analysis of the results thus obtained allows one to assess not only the concentration of the effective active centers on the sorbent, but also all known characteristics of antibody affinity: the average association constant K0, the common association constant Kt, the geometric association constant Kg, the average association constants which determine the affinity of different antibody groups. The use of antigenic immunosorbent permits one to determine the value of the average internal association constant K0. The determination of antibody affinity in hyperimmune antiplague sera by means of immunosorbents and red blood cells coated with capsular antigen has resulted in obtaining similar values of affinity indices.     

Algal single cell protein from wastewater treatment and renovation process

A Source of high-quality protein for animal feed, based upon algae recovered in the process of upgrading waste oxidation pond effluents and promising to be particularly economical, is being developed at the Technion. Unlike other types of single cell protein(SCP), the algal protein does not have to return the full production cost but only that of concentration and final processing. The balance is shared by the value of waste disposal and the reclaimed water. Whereas such systems as activated sludge require considerable mechanical energy to supply the oxygen needed for aerobically degrading organics in wastewater, oxidation ponds utilize solar energy for that purpose. The sludge obtained when their effluents are clarified consists largely of algae, bacteria, fungi, and zooplankton in relative proportions varying with operating conditions, and contains 40–60%(dry basis) high-quality protein. The high rate oxidation pond (a particularly intensive type of pond) produces on the average 34 g/m²7sol;day solids, or over 100 tons/ha (hectare) annually. Two clarification routes have been found promising: centrifugation and alum flocculation followed by frothflotation. The latter route is less expensive in terms of both fixed and operating cost, and gives clarified effluent of higher quality, which can be seasonally stored with minimal eutrophication because the aluminum removes most of the phosphate from the effluent. A good product has been obtained by drum-drying the concentrate, and preliminary feeding tests have indicated that it can replace at least 1/4 of the soymeal in broiler rations and 2/3 of the fishmeal in carp feed. No ill effect of the aluminum in the product recovered by alum flocculation has been found so far a process for removing and recycling the aluminum has been developed nonetheless, in case ill effects do show up in further tests. The combined value of the benefits derived from a system centered around the high-rate oxidation pond with clarification by flocculation–flotation, in terms of waste treatment by alternative means, potable water saved, and soymeal replaced, significantly exceeds estimated cost.     

Elemental diet as primary treatment of acute Crohn's disease: a controlled trial.

Acute exacerbations of Crohn''s disease are usually treated with prednisolone or potentially more toxic immunosuppressive drugs or by surgery. In pilot studies replacing the normal diet by a protein free elemental diet also induced remission. A controlled trial was therefore conducted in which 21 patients acutely ill with exacerbations of Crohn''s disease were randomised to receive either prednisolone 0.75 mg/kg/day or an elemental diet (Vivonex) for four weeks. Assessment at four and 12 weeks showed that the patients treated with the elemental diet had improved as much as and by some criteria more than the steroid treated group. Elemental diet is a safe and effective treatment for acute Crohn''s disease.     

Poly(ADP-ribose) has a branched structure in vivo

We have searched for the presence of branching in the chromosomal polymer poly(ADP-ribose) as it occurs in vivo. Treatment of the polymer with phosphodiesterase asnd phosphomonoesterase results in the conversion of internal residues to the nucleoside ribosyladenosine and the conversion of points of branching to diribosyladenosine. We have detected diribosyladenosine in digests of the polymer derived from carcinogen-treated SV40 virus-formed 3T3 cells and in normal rat liver, kidney, and spleen. The frequency of residues involved in branching varied from 0.8 to 1.6 mole % over a 50-fold range of total levels of poly(ADP-ribose). Thus, branching seems to be a general feature of poly(ADP-ribose) as it occurs in vivo.     

Cell cycle arrest induced by theophylline in root meristem of Haplopappus gracilis

Theophylline, an inhibitor of cyclic nucleotide phosphodiesterase, induced a block of the cell cycle in G₁, a temporary arrest in G₂ and 70% decrease in the uptake of labelled thymidine in roots of Haplopappus. These effects are compared to those previously found with aminophylline and discussed in view of the possible involvement of cAMP in the regulation of the cell cycle in plants.     

Inhibition of elongation and H+ and K+ transport by the phosphodiesterase inhibitor aminophylline in plant tissue

Aminophylline, an inhibitor of cyclic nucleotide phosphodiesterase (EC 3.1.4.17), inhibits elongation and correlated H⁺ and K⁺ transport in embryos of Haplopappus gracilis and in pea internode segments. Moreover, the drug strongly inhibits the stimulation of these processes by fusicoccin and indole-3-acetic acid and reduces passive permeability of the membrane. The possible mechanisms of action of aminophylline are discussed.Abbreviations cAMP adenosine 3:5-cyclic monophosphate - FC fusicoccin - IAA indole-3-acetic acid - MES 2-N-morpholinoethanesulfonic acid - PDE cyclic nucleotide phosphodiesterase