Inhibition of the graft-versus-host response by BCGcw-induced suppressor cells or prostaglandin E1

Immunization of C57BL/6 mice with BCGcw stimulated a population of "suppressor cells" which had a decreased capacity to induce the graft-versus-host response. The graft-versus-host response was quantitated using the Simonsen splenomegaly assay. F1 mice (C57BL/6 X CBA) were inoculated intraperitoneally with 1 X 10(8) parental (C57BL/6) or (CBA) spleen cells. The F1 mice were sacrificed 13 days later and the resulting splenomegaly was 3-4 times the normal amount. F1 mice which were injected with parental BCGcw-primed C57BL/6 spleen cells had a 50% inhibition of splenomegaly, whereas BCGcw-primed CBA spleen cells (a strain which does not develop suppressor cells) did not show this inhibition. In vitro results also confirmed that only C57BL/6 mice and not CBA mice developed suppressor cells after BCGcw immunization. A second study showed that X-irradiated (1000 R) BCGcw-primed "suppressor cells" could inhibit splenomegaly caused by the inoculation of normal parental C57BL/6 cells into F1 mice. The mechanism by which BCGcw-primed "suppressor cells" caused this inhibition of splenomegaly was delineated and found to be dependent upon the secretion of prostaglandin (PGE-1). Indomethacin and aspirin, potent inhibitors of prostaglandin synthesis, blocked the activity of C57BL/6 BCGcw "suppressor cells" and splenomegaly resulted. Systemic administration of the prostaglandin (15S)-15-methyl PGE-1 reduced splenomegaly approximately 50% in F1 mice which were injected with C57BL/6 or CBA cells. These results indicated that immunization with BCGcw stimulated a population of "suppressor cells" which could cause a decrease in graft-versus-host response and that the secretion of prostaglandin was responsible for this inhibition.     

Cerebrospinal fluid-contacting neurons of the central canal and terminal ventricle in various vertebrates

Cell and Tissue Research - Cerebrospinal fluid (CSF)-contacting neurons were studied by means of electron microscopy in the spinal cord and/or terminal ventricle of the ray, Raja clavata...     

High Bulk Diet for Diverticular Disease of the Colon

In the past century diverticular disease of the colon has changed from being almost unknown to becoming the most common disease of the colon. Studies in Britain indicated that the pathological basis of the disease is a thickening of the colonic musculature, with diverticulosis and diverticulitis developing because of increased intracolonic pressures generated by the thickened colon wall. This pressure can be sharply reduced by increased colonic bulk. Geographical and anthropological data reveal that diverticular disease results from Western civilization''s food habits, specifically the reduced fiber content in food. There is evidence that increasing the dietary intake of fiber by the addition of bran can prevent formation of diverticula and relieve the symptoms of established disease. Large scale studies are recommended both as treatment and to further test the validity of this concept.     

Branched-chain glycosyl α-amino acids : Part II. Synthesis of 2-D- and 2-L-(3-deoxy-1,2:5,6-di-O-isopropylidene-α-D-glucofuranos-3-yl)glycine. Analogs of the sugar moiety of the polyoxins

Stereospecific hydroxylation of 3-deoxy-1,2:5,6-di-O-isopropylidene-3-C-trans-and 3-C-cis-(methoxycarbonylmethylene)-α-D-ribo-hexofuranose (2 and 3, respectively), with potassium permanganate in pyridine afforded 3-C-[S- and R-hydroxy-(methoxycarbonyl)methyl]-1,2:5,6-di-O-isopropylidene-α-D-glucofuranose, (6 and 7, respectively), in a combined yield, after chromatography, of 43%. Selective formation of monomethanesulfonates (9a and 10a) and p-toluenesulfonates (9b and 10b), followed by treatment with sodium azide and reduction of the azide, afforded the methyl 2-D-(and 2-L-)(3-deoxy-1,2:5,6-di-O-isopropylidene-α-D-glucofuranos-3-yl)-glycinates (12a and 13a, respectively). Basic hydrolysis of the latter compounds yielded 2-D- and 2-L-(3-deoxy-1,2:5,6-di-O-isopropylidene-α-D-glucofuranos-3-yl)glycine (12b and 13b, respectively). The structures of the glycosyl amino acids were correlated with that of L-alanine by circular dichroism.     

Immunologic and clinical improvement of progressive coccidioidomycosis following administration of transfer factor

Three patients with progressive coccidioidomycosis were given preparations of transfer factor (TF). Adverse reactions to TF were minimal. Following TF administration two of these patients had prolonged clinical remissions in their coccidioidal disease. Cellular immune responses were sequentially evaluated by coccidioidininduced delayed-type skin tests, lymphocyte blast transformation and macrophage inhibition factor production (MIF). These three patients each exhibited different cellular immune patterns before and after TF administration. Two patients converted their coccidioidin skin tests, and one converted lymphocyte transformation response to coccidioidin. Also, TF apparently favorably affected the MIF response in all three patients.     

DISTRIBUTION OF PEROXISOMES (MICROBODIES) IN THE NEPHRON OF THE RAT : A Cytochemical Study

The distribution of peroxisomes (microbodies) in the rat nephron was studied cytochemically, using glutaraldehyde- or formaldehyde-fixed tissue, by means of α-hydroxy acid oxidase activity in light microscopy or oxidation of 3,3'-diaminobenzidine (DAB) at pH 9 in both light and electron microscopy.The two cytochemical methods show peroxisomes to be nearly sperical particles found only in cells of the proximal convoluted tubule. Lysosomes were identified in the same or parallel sections, with β-glycerophosphate or 5'-cytidylic acid as substrate. They are found in all cells of the nephron. These cytochemical methods visualize the two organelles for light microscopy; they also permit unequivocal differentiation of all kidney peroxisomes from lysosomes in electron micrographs. Peroxisomes are larger and more reactive in the cells of the pars descendens (P₃ segment) of the proximal convolution, located in the outer medulla and medullary rays, than in the cells of the pars convoluta (P₁ and P₂ segments), situated in the cortex. In contrast, lysosomes are much smaller in the P₃ segment and larger and more reactive in the P₁ and P₂ segments. In all cells of the proximal convolution, peroxisomes tend to be concentrated nearer the base of the cells than do lysosomes. Mitochondria in P₃ cells also show low levels of DAB oxidation at pH 6, in contrast to those in P₁ and P₂ cells. The possibility is discussed that P₃ cells possess an extramitochondrial means of oxidation in which peroxisome oxidases play an important role.     

SYNTHESIS OF RNA IN NEURONS OF THE HYPOGLOSSAL NERVE NUCLEUS, AFTER SECTION OF THE AXON, IN MICE

Synthesis of RNA in neurons of the hypoglossal nerve nucleus after axonal section was studied by means of [5-³H]uridine administration and radioautographic counting techniques in mice. The results of the experiments were evaluated by counts of silver grains over the nucleoplasm and cytoplasm of the neurons. RNA synthesis was greater in neurons after axonal section, and this increase was evident from 12 hr after the operation. The greatest increases in the operated side were observed in the 1st, 2nd and 3rd days after operation. In the 7th and 14th days RNA synthesis was still greater in the hypoglossal nucleus of the sectioned nerve but the difference in the control nucleus was not so striking. In the 30th day synthesis of RNA in left and right hypoglossal nuclei was comparable.     

Physiology of a choline-requiring strain of Torulopsis pintolopesii

Summary A choline-requiring strain of Torulopsis pintolopesii when growing on choline-methyl-¹⁴C or choline-methyl-³H excretes the radioactivity incorporated in the first 24–48 h of incubation up to ca. 85–95% of the radioactivity added at the beginning of the incubation. The addition of non-radioactive methionine did not interfere with the uptake and excretion of radioactivity from choline-Me-¹⁴C. Radioactive methyl group of methionine previously incorporated by growing cells of T. pintolopesii on varying concentrations of choline was not excreted in appreciable amounts. No evidence was obtained for the oxidation of choline to betaine, degradation to trimethylamine, or net incorporation of labelled choline into lecithin. The occurrence of a new pathway for the utilization of choline in yeasts is suggested. The requirement of choline by T. pintolopesii is explained tentatively by the formation and excretion of a compound containing the carbon and hydrogen atoms from the methyl groups of choline and whose chemical structure still under study, may comprise a heteroside containing mannitol as the polyhydroxylated moiety.