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Rabbits, rats and mice were injected intraperitoneally with 4-hydroxy- 3-iodo-5-nitrophenylacetate (NIP)-chicken globulin. Antibodies to this hapten were assayed in gradient centrifuged fractions or gel filtration fractions of their sera by neutralization of NIP-phage. The 19S antibodies appeared a few days after immunization. Sometimes 7S antibodies appeared simultaneously or after a lag of a few days. Rabbits were injected into the hind footpads with 2,4-dinitrophenyl (DNP)- bovine γ-globulin in complete Freund's adjuvant. Passive haemagglutination, antigen-binding, radioimmunoelectrophoresis and passive cutaneous anaphylactic reactions were applied to the assay of antibody in sera and in ultracentrifugal, electrophoretic and chromatographic fractions of these sera. The γM and γG antibodies appeared simultaneously in the blood on the 5th or 6th day after immunization. The γM antibodies were detected most readily by haemagglutination, but also by radioimmunoelectrophoresis. The γG antibodies were detected on the 5th or 6th day by antigen-binding, radioimmunoelectrophoresis and passive cutaneous anaphylaxis and only later by haemagglutination. The data are discussed with regard to methods for demonstrating the different classes of antibody to haptens, to the organ and cellular origins of antibodies and to the validity of the postulated sequential synthesis of γM and γG antibodies. [ABSTRACT FROM AUTHOR]

A re-investigation has been made of the earlier claim by Simonsen (1957) that grafted immunologically competent cells (ICC) may proliferate indefinitely as evidenced by unlimited transferability of the graft-host splenomegaly in chick embryos. The observation was repeated, but the original interpretation proved untenable. A method of chimaera analysis was developed, based on neutralization of ICC with specific serum antibodies. Cells and antisera were mixed in vitro immediately before i.v. injection into the embryo and the neutralization assessed quantitatively by the reduction of spleen enlargement obtained in comparison with ceils plus normal serum. It was found that the 17-day embryo recipient of ICC from an adult bird under- goes an accelerated immunological maturation which in 7 days confers upon its blood and spleen ceils a higher degree of immunological competence, per unit number of cells, than in relevant controls. The first host is thus enabled to cause a GVH-reaction in a new 17-day embryo which, in turn, matures precociously. Hence a cycle is created which permits a serial transfer of splenomegaly for as long as the new host is antigenic to the previous host. The phenomenon was not repeatable with hosts of constant genotype. Accelerated maturation is not a mere antigenic stimulation of the young animal. So far it has only been produced by live cells, and only in conditions where the host is antigenic to the graft. [ABSTRACT FROM AUTHOR]

The pH-dependence of the inhibition of cobalt carbonic anhydrase by three different sulfonamides has been measured employing p-nitrophenyl acetate as substrate. The binding of these inhibitors is linked to two ionizing groups. One of these seems to be identical to the group in the enzyme previously shown to control the catalytic activity. The pK of the second group is characteristic for the individual inhibitor and agrees with pK-values obtained by titration of the sulfonamides. Sulfanilamide and the anionic inhibitor, NO3-, appear to compete for one binding site on the enzyme. When the sulfanilamide inhibition of the CO2-hydration activity was studied by the stopped-flow method, some anomalous behavior was observed. From the initial part of the reactions, apparent noncompetitive inhibition was obtained. The rates increased over a short time period, however, to give essentially a competitive pattern. The results can be explained by assuming that the substrate and the inhibitor are competitive, but that equilibration is not immediately achieved due to a comparatively slow rate of dissociation of the inhibitor from the enzyme. The apparent second order rate constant for the formation of the enzyme-sulfanilamide complex has been estimated as 7 × 104 M-1 sec-1 at pH 7.9 and 25°. In the presence of CO2, the reaction is slower to an extent which is compatible with a competition for a common binding site. A simple, though not unique, mechanism for the sulfonamide inhibition of bovine cobalt carbonic anhydrase, accounting for both rate and equilibrium data, implies the formation of the enzyme-inhibitor complex through a direct reaction of the ionized sulfonamide with the inactive, acid form of the enzyme. [ABSTRACT FROM AUTHOR]

A promotion of expansion of etiolated bean leaf disks by ultraviolet (UV) radiation was confirmed. The optimum conditions for the effect were found to be 5 seconds UV exposure followed by 24 hours of incubation at 25°C and pH 6.2. Macerations and sections of the treated and control disks indicated that the basis of the response was an increase in the number of cells in the UV treated disks. Experiments with indolebutyric acid (IBA) and p-chlorophenoxyisobutyric acid (PCIB) indicated that the UV apparently acted to reduce a superoptimal endogenous auxin level to an optimum level which resulted in promotion of the expansion. [ABSTRACT FROM AUTHOR]

An optical technique for the assay of phosphoglycerate kinase in skin extracts is described. This has been used to confirm the presence of the enzyme in mouse and human skin. The enzyme has been shown to be completely soluble. Its pH-dependence has been examined; a rather flat curve, with a slight peak at pH 6-0, was obtained. [ABSTRACT FROM AUTHOR]

The article reports that neutralizing Coxsackie antibodies arising from natural infections with Coxsackie virus type B3 or B5 were studied in adults and newborn babies. The question whether in man the immune response of newborn babies to new antigenic stimuli is essentially different from that of adults has been approached by immunization with various antigens. The results are contradictory. There are two difficulties inherent in these studies, passively transferred maternal antibody, if present, weakens the response of newborn babies, and while a true primary response is likely in newborn babies, adults may have been in contact with the test antigen earlier, unknown to the experimenter, and give a secondary response.

The article focuses on research into the effect topical sodium fluoride and urea applications has to the incidence of dental caries in Syrian hamster teeth. It states that fluoride in drinking water resulted in a reduction of caries activity in the molar teeth of hamsters. It mentions that urea is believed to reduce dental caries activity through the liberation of ammonium carbonate, resulting in the neutralization of acids produced in dental plaque.

The article presents a study which investigates the solubility of dental enamel in saliva at various hydrogen-ion concentrations. Several past studies on the topic are also discussed, including one which demonstrated the ability of saliva to neutralize an acid phosphate solution in its decalcifying activity and others which have found that saliva is able to completely prevent decalcification by neutralizing lactic and other acids.

The article presents a study examining the ability of saliva to neutralise acids. Several means of influencing the acid-neutralising ability of saliva are discussed, including the introduction of alcoholic liquors or acids to the mouth and movement of the jaws. Foods that influence the ability of saliva to neutralise acids are also discussed, including hard-boiled eggs, roast chicken, and black bread.

1. A report is made on 3,877 peptic ulcers treated, using the concept that at least 14 liters of N/10 hydrochloric acid must be neutralized per day in order to inactivate the corrosive effects of acid in peptic ulcer for a period of more than four months. 2. It is pointed out that only 83.4 per cent of these cases were able to gain granulation tissue on this program and that 7.62 per cent could not be healed by any medical therapy. 3. The use of the roentgenogram as a criterion of the healed ulcer is felt to be inadequate. 4. Criteria are given for defining the healing and healed ulcer. 5. The merits of unrestricted diet in peptic ulcer are enumerated with reference to medical methods which permit its use. 6. The importance of approaching the problem of peptic ulcer in terms of amount of hydrochloric acid to be neutralized per day is accentuated, particularly in complications and short-history gastric ulcer. 7. The inadvertent healing of peptic ulcer in three categories is outlined. 8. Personal interview follow-up on 1,278 patients shows that most of this group remained healed three or more years and evidence is given which excludes them from a "healing by accident" group. [ABSTRACT FROM AUTHOR]

Discusses the use of fortified defatted dry milk protein in treatment of peptic ulcers. Predominant factors as basis for the approach to the problem of peptic ulcer therapy; Importance of the neutralization or reduction of the acid chyme in ulcer therapy; Effects of anticholinergics on the secretory and motor activity of the stomach; Common complaint and manifestation of activity or penetration on several patients included in the study.

The article focuses on the use of bacteriophages as model systems in studying the antigenic properties of viruses. It offers information on the nature of bacteriophages, bacterial viruses discovered by English microbiologist F. W. Twort in 1945, and examines the interaction of these viruses with specific antibody. The neutralization reaction, which is the interaction of one phage with an antibody molecule, and the heterogeneity of bacteriophages are discussed. The article also discusses the serological characteristics of phages and reaction rate of these bacteriophages in antigens.

The article presents information on the process adopted by Cone Mills Corp. to control alkaline textile waste in their textile mill based in the U.S. In the early 1950s, Cone Mills started a research program studying the possibilities of handling the strongly alkaline textile waste biologically. After a detailed study it was decided that biological purification without prior chemical pretreatment or neutralization was both feasible and practical. As an overall conclusion to this research, Cone Mills plants now handle their liquid waste in a number of ways. The study designed a 3 MGD plant, which is the first activated sludge-type plant in the world built to handle alkaline textile waste without neutralization.

The article presents information about the paper "Investigation of the Buffer Capacity and Reaction of the Skin After Use of Modern Cleansing Agents," by B. Werdelmann, that appeared in a previous issue of the journal "Berufsdermatosen." Alkali and acid neutralization are measured and pH values determined after use of synthetic detergents on the forearms of normal test persons. Alkali neutralization is quicker than with toilet soap. Acid neutralization is uninfluenced by detergents. There is rapid restoration of the normal pH after use of detergents. In addition there were a number of incidental findings.

This article reports that from June to November 1965, there were 25 children aged three to 18 months admitted with severe pneumonitis to the Princess Mary Hospital for Children and the Infectious Diseases Unit of Auckland Hospital in Auckland, New Zealand. Of these, 18 were boys and seven were girls. Identification of the causative adenovirus was from pharyngeal secretions of 21 children, and also from fluid obtained by lung puncture in two cases. All adenovirus isolates were serologically identified as type 21 by tissue culture neutralization tests. Respiratory syncytial virus was not recovered. Bacteriologic studies of throat swabs taken on admission showed no pathogens in 16 cases; a diversity of other organisms were in the remainder.

The article focuses on the study "Sur la Digitalis purpurea, plante calcifuge," by R. Chodat which focused on the calcifuge character of foxglove. In this paper, the author discusses the results of certain experiments which described the nature of the effect of lime on the growth of Digitalis purpurea. He observed that when basic carbonate of magnesium is added to the lime, the inhibitory action is increased. On the other hand, if dolomite is added to the original soil the retarding effect upon growth is less marked. The author concludes that the action of lime is due to its alkalinity in neutralising the acids of humus.