Pilot-scale production of group a and group C meningococcal polysaccharide immunogens

Methods have been developed for the pilot-scale production of group A and group C meningococcal polysaccharide immunogens based on the meningococcal strains, the medium, and the basic processing procedures used by Gotschlich et al. Physical and chemical assays on the final products obtained on a pilot-scale level indicate that these purified polysaccharides are entirely comparable to the Gotschlich preparations which proved to be immunogenic in man.     

Extraction and characterization of IgG Fc receptors from group C and group G streptococci

Immunoglobulin G (IgG) Fc receptors (FcRs) were extracted by proteolytic digestion of four strains each of group C and group G streptococci. The solubilized proteins were analyzed in Western blots and multiple IgG-binding bands were obtained. The banding patterns of some of the strains were very similar, but this property was independent of which streptococcal group the strains belonged to. Highly purified FcRs were prepared from one group C and one group G strain. The 13 N-terminal amino acids were determined, and found to be identical, whereas comparison with the sequence of staphylococcal protein A did not reveal any homology. The isolated streptococcal FcRs also appeared closely related antigenically and functionally. Thus, both molecules were capable of inhibiting each others binding to immobilized IgG, and the radiolabelled group G FcR was completely inhibited from binding to IgG by an antibody to the group C FcR. Finally, in a direct binding assay both proteins were capable of reacting to a similar degree with a wide variety of IgGs, thereby demonstrating the great potential of streptococcal FcRs as tools for binding and detection of IgG antibodies.     

Epigenetic regulation of cardiac development and function by polycomb group and trithorax group proteins

Heart disease is a leading cause of death and disability in developed countries. Heart disease includes a broad range of diseases that affect the development and/or function of the cardiovascular system. Some of these diseases, such as congenital heart defects, are present at birth. Others develop over time and may be influenced by both genetic and environmental factors. Many of the known heart diseases are associated with abnormal expression of genes. Understanding the factors and mechanisms that regulate gene expression in the heart is essential for the detection, treatment, and prevention of heart diseases. Polycomb Group (PcG) and Trithorax Group (TrxG) proteins are special families of chromatin factors that regulate developmental gene expression in many tissues and organs. Accumulating evidence suggests that these proteins are important regulators of development and function of the heart as well. A better understanding of their roles and functional mechanisms will translate into new opportunities for combating heart disease.     

Within group and between group variation expected in human behavioral characters

The empirical evidence for genetic variation in normal human behavior may be ambiguous and limited to special traits. However, population genetics has produced experimental evidence and theoretical arguments for the existence of genetic variation in all biological traits. These conclusions apply to human behavior because it has a biological basis; it depends on gene-controlled mechanisms.The certainty of intra-population genetic variation ensures the presence of heritable differences between populations. At least six processes operate in human populations to translate individual genetic variation into population differences. Three are selective: natural selection, selective membership in an isolated, and phenotypic assortative marriage. Three are unselective: group migration, random inbreeding or sampling deviations, and systematic inbreeding. Selective processes operate directly on phenotypic characteristics, whether monofactorial or polygenic. Unselective processes affect genes singly and randomly, thus have their most significant effects on simple Mendelian traits. Most differences between populations in quantitative behavioral characters probably result from selective processes.     

Secretors and nonsecretors of group antigens

Summary Data of different authors on the content of group antigenic substances (A, B) in the body fluids of man are reported.The author investigated group antigens in the amniotic fluid. In all cases group substances identical to those of fetal blood were revealed in the amniotic fluid, and, group antigens, present in the child's blood were always revealed in the corresponding samples of the amniotic fluid.Thus, Schiff and Sasaki's conception, which is shared by the majority of the foreign and a number of Soviet authors, on the possibility of dividing all persons into secretors and nonsecretors was not confirmed experimentally in respect of the amniotic fluid.Establishment of the fact of the constant presence in the body fluids of group substances, identical to blood hemagglutinogenes of that individual, although those only of theoretical interest, may be of practical significance, particularly in the medicolegal field.Presented by Active Member AMN SSSR, N. M. Zhukov-Verezhnikov Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 57, No. 1, pp. 71–74, January, 1964     

Effect of intrathecal clonidine on group I and group II oligosynaptic excitation in paraplegics

We investigated the possibility that a change in transmission in group II pathways contributes to the spasticity of patients with spinal lesions. Thirteen patients were tested by measuring the quadriceps stretch reflex (Ashworth scale), the threshold of the quadriceps H reflex, and the oligosynaptic facilitation of the quadriceps H reflex elicited by volleys to groups I and II afferents in the common peroneal nerve (CPN). All these tests were performed before and after intrathecal injection of clonidine (60 μg). Early group I CPN-induced excitations occurred in 13 patients, and late group II CPN-induced excitations in 12. Both facilitations were, on average, significantly greater than those reported for normal subjects, but these increases were not correlated with the clinically assessed spasticity. Clonidine caused a constant, prolonged and dramatic decrease in spasticity, but did not alter the threshold of the quadriceps H reflex. CPN-induced group I and group II non-monosynaptic excitations of quadriceps motoneurones were significantly decreased, although they did not return to normal values. These results provide a further indication that group II pathways gives rise to the heteronymous late CPN-induced excitation. The pathophysiological role of a change in transmission in group II pathways in spasticity is discussed. Electronic Publication     

Two novel superantigens found in both group A and group C Streptococcus

Two novel streptococcal superantigen genes (speL(Se) and speM(Se)) were identified from the Streptococcus equi genome database at the Sanger Center. Genotyping of 8 S. equi isolates and 40 Streptococcus pyogenes isolates resulted in the detection of the orthologous genes speL and speM in a restricted number of S. pyogenes isolates (15 and 5%, respectively). Surprisingly, the novel superantigen genes could not be found in any of the analyzed S. equi isolates. The results suggest that both genes are located on a mobile element that enables gene transfer between individual isolates and between streptococci from different Lancefield groups. S. equi pyrogenic exotoxin L (SPE-L(Se))/streptococcal pyrogenic exotoxin L (SPE-L) and SPE-M(Se)/SPE-M are most closely related to SMEZ, SPE-C, SPE-G, and SPE-J, but build a separate branch within this group. Recombinant SPE-L (rSPE-L) and rSPE-M were highly mitogenic for human peripheral blood lymphocytes, with half-maximum responses at 1 and 10 pg/ml, respectively. The results from competitive binding experiments suggest that both proteins bind major histocompatibility complex class II at the beta-chain, but not at the alpha-chain. The most common targets for both toxins were human Vbeta1.1 expressing T cells. Seroconversion against SPE-L and SPE-M was observed in healthy blood donors, suggesting that the toxins are expressed in vivo. Interestingly, the speL gene is highly associated with S. pyogenes M89, a serotype that is linked to acute rheumatic fever in New Zealand.     

Comparison of type III Fc receptors associated with group C and group G streptococci

The type III Fc receptors present on or secreted by a series of group C and G streptococcal strains were studied. All strains capable of binding radiolabeled human IgG were shown to do so via an antigenically related Fc receptor. Treatment of any of the bacterial strains with papain or trypsin resulted in solubilization of Fc receptor activity. The pattern of Fc receptor activity recovered following enzyme treatment was not uniform. Differences were observed both between group C and G strains as well as within group C and G strains. Analysis of secreted Fc receptors indicated the presence of five molecular forms of Fc receptor. Each form was present at some level in the supernatant of every group C and G strain studied. The relative concn of each form of receptor secreted varied from strain to strain. The Fc receptor activity secreted by each strain demonstrated a similar affinity for the Fc region of human IgG and all were antigenically related. These results suggest that there is a family of closely related Fc receptors associated with group C and G streptococcal strains.     

Bacteriological and serological aspects of group a streptococcal pharyngotonsillitis caused by group a streptococci

Several bacteriological and serological variables were studied in connection with a clinical treatment trial in 212 patients with group A streptococcal pharyngotonsillitis. Anaerobic incubation was not superior to incubation in 5 % CO₂ in air for the detection of group A streptococci. Saliva cultures were inferior to conventional throat cultures in detecting group A streptococci. No strains from patients with recurrences were found to be tolerant to penicillin. In several patients (all asymptomatic), group C and G streptococci were found in follow-up cultures. Group A streptococci serology was more often positive after two months than after one month, also in patients without recurrence.     

Sialidase activity of the "Streptococcus milleri group" and other viridans group streptococci

Viridans group streptococci were examined for the production of sialidase (neuraminidase) activity, using the fluorescent substrate 4-methylumbelliferyl-alpha-D-N-acetylneuraminic acid in a simple and rapid (15-min) assay. Sialidase was produced by all strains of Streptococcus oralis and S. intermedius and by a majority of S. mitis strains. S. mutans, S. sobrinus, S. gordonii, S. sanguis, S. vestibularis, S. salivarius, S. anginosus, S. constellatus, "S. parasanguis," and the "tufted fibril group" were uniformly negative. Sialidase production may be a useful characteristic to assist in the identification of viridans group streptococci.     

Individual and group training program

We describe the experience of a didactic analysis group during a 3-year period in the Academy of Analytical Psychotherapy placing special emphasis on the training of the psychoanalyst, who, apart from carrying out his individual analysis, must complement it with group training. The advantages of the group analysis are given particular attention when evaluating the training of the candidate from the point of view of the psychoanalyst and the 6 doctors who have received this education. In this type of training for individuals and groups the program aims at a deeper study of the aspects of narcissism, the formation of the self and the social ego which we consider to be the fundamental elements in the development of this didactic experience.