N-(substituted-phenyl)-D-glycopyranosylamines and their O-acetyl derivatives as potential modifiers of the formation of glycosaminoglycans

D-Arabinosyl, D-ribosyl, D-glucosyl, D-galactosyl, D-mannosyl, and L-rhamnosyl N-glycosides of p-aminobenzoic acid and their O-acetyl derivatives have been synthesized, and their ability to (a) inhibit the replication of cultured B16 melanoma cells and (b) modify the synthesis of glycosaminoglycans by these neoplastic cells have been evaluated. The most cytotoxic compound of the series was N-(p-carboxyphenyl)-2,3,4-tri-O-acetyl-D-arabinopyranosylamine (8), which produced 50% inhibition of cellular proliferation at a concentration of 4 microM; a number of other compounds were relatively cytotoxic, causing 50% inhibition of cell replication at levels of 18 to 49 microM. These effects were not due to modification of glycosaminoglycan biosynthesis, since these compounds were ineffective as inhibitors or initiators of the formation of these macromolecules.

Synthesis of N-(Substituted-phenyl)-D-xylopyranosylamines as potential modifiers of the formation of glycosaminoglycans

N-(Substituted-phenyl)-D-xylopyranosylamines and their O-peracetyl derivatives have been synthesized and tested for their ability (a) to inhibit the replication of cultured B16 melanoma cells and (b) to modify the synthesis of glycosaminoglycans by these neoplastic cells. The most cytotoxic compound synthesized was N-(p-methoxyphenyl)-D-xylopyranosylamine (6), which produced 50% inhibition of cellular proliferation at a concentration of 2 microM; a number of other compounds were relatively cytotoxic, causing 50% inhibition of cell replication at levels of 12 to 25 microM. Several of the synthesized xylosides appeared to be capable of serving as artificial initiators of glycosaminoglycan synthesis, with the most active agents causing approximately 2- to 4-fold increases in the incorporation of [35S]sulfate into the glycosaminoglycans of B16 melanoma cells excreted into the culture medium.

Distribution of surface anionic sites on mouse hybrid myelomas

The surface anionic site distribution on membranes of a monoclonal antibody-producing hybridoma cell line, and its two parental cells: normal spleen cells of immunized BALB/c mice and cells from a mouse myeloma line (NS-1), were investigated with the aid of the cationized ferritin (CF) labelling method, following glutaraldehyde/formaldehyde fixation of cells. The patch-like CF distribution on the hybridoma cells is similar to that of the NS-1 myeloma cells, but distinct from the even and continuous CF distribution of the immunized and nonimmunized normal spleen lymphocytes. The similarity in the formation of patch-like CF heaps, both on myeloma and hybrid cells is discussed in respect to the surface charge characteristic determined by cell fusion.

Monoclonal antibodies against immunodeterminants associated with the alpha and beta subunits of human chorionic gonadotropin

Spleen cells of BALB/c mice immunized with human chorionic gonadotropin (HCG), a glycopeptide hormone composed of two nonidentical alpha and beta subunits, were fused with NS-1 mouse myeloma cells. Two hybrid cell lines, cone PC2 and clone PD3 secreting monoclonal antibodies (McAb) to HCG were isolated. With the aid of a double antibody radioimmunoassay it was established that PC2-McAb recognizes an immunodeterminant associated with beta-HCG subunit, whereas, PD3-McAb recognizes an epitope present on the alpha-HCG subunit. Both monoclonal antibodies showed an affinity constant of approximately 5 X 10(10) L/M. Because of these immunological characteristics, only PC2-McAb specifically reacts with HCG and shows cross-reactivities of less than 0.1% to other related human glycopeptide hormones. On the other hand, using a hemagglutination test based on antibody induced agglutination of sheep red blood cells coated with HCG, it was shown that only PD3-McAb is capable of inducing a positive reaction, although both monoclonal antibodies have a similar binding capacity to the coated cells. The potential of these two new monoclonal reagents for the qualitative detection and quantitative determination of HCG in human biological fluids is discussed.

The effect of transmitter antagonists on phasic respiratory neurons

The activity of inspiratory neurons in the nucleus tractus solitarius (NTS) and of expiratory neurons in the nucleus retroambigualis (RNA) was recorded during the iontophoresis of L-glutamate, bicuculline, and strychnine in chloralose-urethane-anesthetized cat. Bicuculline methoxide caused increased activity of NTS and NRA neurons during their active or burst phases. Neither bicuculline nor strychnine caused increased activity during the silent phases of NTS or NRA neurons. When neurons were driven to fire during their silent phase by L-glutamate, the application of bicuculline methoxide caused a diminution of the evoked activity. It is concluded that both inspiratory and expiratory neurons receive inhibitory inputs during both their active and silent phases. Gamma-aminobutyric acid appears to be gating both the excitatory and inhibitory information to NTS and NRA neurons. Strychnine was generally ineffective in changing the firing patterns of inspiratory and expiratory neurons suggesting a limited role of glycine, taurine, and L-alanine in the respiratory network.

Detection of genetic variation with radioactive ligands. IV. X-linked, polymorphic genetic variation of thyroxin-binding globulin (TBG)

A genetically determined, polymorphic electrophoretic variant of thyroxin-binding alpha-globulin (TBG) is found in sera from populations of African and Oceania origin, although not in Caucasians nor Orientals. The TBG polymorphism is inherited in X-linked fashion, based on data from American blacks, and thus provides an X-chromosome marker with a relatively high gene frequency in this ethnic group (frequency of the slow allele, TBGs, is 11%). This slow variant should prove valuable in expanding the map of the X chromosome and in linkage studies. An additional family exhibiting X-linked TBG deficiency is also described.

Waardenburg's syndrome: variations in expressivity

Twenty-seven subjects with a family history of Waardenburg's syndrome were examined with respect to 18 specific characteristics of the syndrome, with particular emphasis in identifying the spectrum of the phenotypic expression of affected persons. Our results indicate that patients with the syndrome may have a variety of clinical signs, and an accurate diagnosis will therefore depend on a thorough and pertinent family history and physical examination.

The acupuncture treatment of low back pain: a randomized controlled study

The acupuncture treatment situation was beneficial to the majority of people with low back pain. This was shown by the use of short-term controls and long-term controls, although the latter were not intended in the study design. After acupuncture, there was a 51% pain reduction in the average pain score in the Immediate Treatment Group. The short-term controls, the Delayed Treatment Group, had no reduction whatsoever in their pain scores at the comparable followup period. Later, the Delayed Treatment Group bere also treated by acupuncturists, and reported 62% less pain. When these two treatment groups were compared at 40 weeks with long-term controls (Inadequate Treatment Group), the Inadequate Treatment Group still had the same pain scores, on the average, as when they enrolled in the study. Both treatment groups, on the average, had 30% lower pain scores. Furthermore, 58% of the treatment groups felt that they were definitely improved at 40 weeks, while only 11% of the Inadequate Treatment Group felt definitely improved at 40 weeks.

Effects of excitatory and inhibitory amino acids on phasic respiratory neurons

The responsiveness of phasically active brainstem respiratory neurons to several amino acids was investigated in cats under Dial anesthesia. Four-barreled microelectrodes were used to extrude iontophoretically the putative neurotransmitters L-glutamate, L-asparatate, glycine, and gamma-aminobutyric acid (GABA), L-glutamate and L-aspartate caused increased activity when applied to either inspiratory or expiratory neurons and appeared to be equal in efficacy. Likewise, GABA and glycine depressed ongoing phasic neural activity of both inspiratory and expiratory units. In this case, however, the dosage of GABA required to produce a given depression was significantly less than the required dosage of glycine. These findings support the hypothesis that L-glutamate and/or L-aspartate may act as excitatory neurotransmitter agents at the synapses of brainstem respiratory neurons and conversely, GABA may act as the natural inhibitory neurotransmitter.