Na+-sensitive component of 3-O-methylglucose uptake in frog skeletal muscle

Summary A Na⁺-sensitive uptake of 3-O-methylglucose (3-O-MG), a nonmetabolized sugar, was characterized in frog skeletal muscle. A removal of Na⁺ from the bathing solution reduced 3-O-MG uptake, depending on the amount of Na⁺ removed. At a 3-O-MG concentration of 2mm, the Na⁺-sensitive component of uptake in Ringer's solution was estimated to be about 26% of the total uptake. The magnitude of Na⁺-sensitive component sigmoidally increased with an increase of 3-O-MG in bathing solution, whereas in Na⁺-free Ringer's solution the uptake was proportional to the concentration. The half saturation of the Na⁺-sensitive component was at a 3-O-MG concentration of about 13mm, and the Hill coefficient was 1.4 to 1.6. Phlorizin (5mm), a potent inhibitor specific for Na⁺-coupled glucose transport, reduced the uptake in a solution containing Na⁺ to the level in Na⁺-free Ringer's solution. Glucose of concentrations higher than 20mm suppressed 3-O-MG uptake to a level slightly lower than that in Na⁺-free Ringer's solution. These observations indicate that there are Na⁺-coupled sugar transport systems in frog skeletal muscle which are shared by both glucose and 3-O-MG.     

Axial ligation of nitrogenous bases to five-coordinate chloro-meso-tetraphenylporphyrinatochromium(III)

The axial ligations of nitrogenous bases to the five-coordinate chloro-meso-tetraphenylporphyrinatochromium(III) [Cr(III)(TPP)(Cl)] were studied in a non-coordinating solvent, dichloromethane (CH₂Cl₂), by spectrophotometric methods. A correlation exists between log K for the axial ligation:

and pK_a for the N-donor ligand. This correlation suggests that ligand to metal σ bonding contributes to the complex formation, rather than does metal to ligand π back-donation.     

Morphine-Induced Changes in Histamine Dynamics in Mouse Brain

The effect of the acute morphine treatment on histamine (HA) pools in the brain and the spinal cord was examined in mice. Morphine (1-50 mg/kg, s.c.) administered alone caused no significant change in the steady-state levels of HA and its major metabolite, tele-methylhistamine (t-MH), in the brain. However, depending on the doses tested, morphine significantly enhanced the pargyline (65 mg/kg, i.p.)-induced accumulation of t-MH and this effect was antagonized by naloxone. A specific inhibitor of histidine decarboxylase, alpha-fluoromethylhistidine (alpha-FMH) (50 mg/kg, i.p.), decreased the brain HA level in consequence of the almost complete depletion of the HA pool with a rapid turnover. Morphine further decreased the brain HA level in alpha-FMH-pretreated mice. Morphine administered alone significantly reduced the HA level in the spinal cord, an area where the turnover of HA is very slow. These results suggest that the acute morphine treatment increases the turnover of neuronal HA via opioid receptors, and this opiate also releases HA from a slowly turning over pool(s).     

Reverse effect of gram-positive bacteria vs. gram-negative bacteria on adjuvant-induced arthritis in germfree rats

Germfree (GF) F344 rats developed severe adjuvant-induced arthritis with a 100% incidence after a single intradermal injection of heat-killed Mycobacterium bovis (BCG). Specific pathogene-free (SPF) rats developed less severe arthritis with a lower incidence. The rats colonized with Escherichia coli or Bacteroides developed mild disease comparable to that in SPF rats. The rats colonized with Bifidobacterium, Propionibacterium acnes, Lactobacillus casei, L. fermentum, L. murini, and L. acidophilus developed more severe disease than that in GF rats. Furthermore, the rats colonized with a mixture of E. coli and the above lactobacilli developed very mild disease similar to that in SPF rats. These results suggest that gram-negative bacteria, such as E. coli and Bacteroides, may suppress the disease, possibly through their lipopolysaccharides, and may be responsible for the lower susceptibility of SPF rats; gram-positive bacteria, such as Bifidobacterium, P. acnes, and lactobacilli, may enhance the disease, possibly through their peptidoglycans; and E. coli may play a dominant role in modulating the development of adjuvant-induced arthritis.     

Isolation and reconstitution of the iron-sulfur protein in ubiquinol-cytochrome c oxidoreductase complex. Phospholipids are essential for the integration of the iron-sulfur protein in the complex

An iron-sulfur protein has been purified from beef heart ubiquinol-cytochrome c oxidoreductase (Complex III) of the mitochondrial respiratory chain by phenyl-Sepharose column chromatography and Sephacryl S-200 gel chromatography. Depletion of most of the endogenous phospholipids in the complex was a prerequisite to the dissociation of the protein from the complex in the former chromatography. The iron-sulfur protein was nearly homogeneous as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and contained 76 ng atoms of nonheme iron and 66 nmol of acid-labile sulfide/mg of protein. When this preparation was incubated with an iron-sulfur protein-depleted complex in the presence of soybean phospholipids, the enzymic activity was restored up to 90% of that of the parent Complex III, whereas the recovery of the activity was marginal in the absence of the phospholipids. Thus it is clear that the iron-sulfur protein is integrated into the complex with the aid of phospholipids.     

Correlations in one-dimensional fully developed chaos

Correlations in the baker map and the tent map as examples of one-dimensional, fully developed chaos are considered. It is shown, utilizing symbolic dynamical systems derived from these maps, that the vanishing second-order correlation function is not sufficient to guarantee uncorrelatedness. Importance of the higher-order, especially third-order, correlation functions is emphasized for chaotic systems. In search of the quantities that grasp correlational behaviors as a whole in chaotic systems, it is proposed to use the fixed-separation correlation integral, which is a modified quantity of the usual correlation integral devised to calculate the fractal dimension of strange attractors, for these maps. It is shown that the new quantity contains all the even-number orders of autocorrelation function that are commonly considered.     

The Lyt phenotype of the T cells responsible for in vivo tumor rejection in syngeneic mice

Summary Spleen cells of BALB/c mice hyperimmunized with a transplantable methylcholanthrene-induced sarcoma Meth A (Meth A-Im-SPL) inhibited the growth of Meth A tumor in vivo in a tumor neutralizing test. Meth A-Im-SPL did not neutralize another antienically distinct sarcoma, Meth 1, indicating that the antitumor activity is tumor specific. Lyt-1⁺2^– cells of Meth A-Im-SPL (Im-Lyt-1⁺2^–) were the effectors since in vitro treatment of Meth A-Im-SPL with anti-Thy 1.2 or anti-Lyt 1.2 antibody plus complement completely abrogated their neutralizing activity, whereas treatment with anti-Lyt 2.2 plus complement did not. To further confirm the effector activity of Im-Lyt-1⁺2^– cells, T cell subpopulations were separated from Meth A-Im-SPL by the panning method. The purified Im-Lyt-1⁺2^–, but not Im-Lyt-1⁺2⁺ cells neutralized the tumor in athymic nu/nu mice as efficiently as in +/+ mice, suggesting that the donor Im-Lyt-1⁺2^– cells but not recipient T cells were primarily responsible for neutralizing the tumor. The present study, however, did not exclude the possible contribution of recipient T cells to the tumor neutralization and this is open to further investigation.Abbreviations Meth A-Im-SPL Meth A-immune mouse spleen cells - Meth 1-Im-SPL Meth 1-immune mouse spleen cells - sIg⁺ cells surface immunoglobulin positive cells - moAb monoclonal antibody     

Effect of Streptococcus faecalis BIO-4R on intestinal flora of weanling piglets and calves.

The effect of oral administration of Streptococcus faecalis BIO-4R, an antibiotic-resistant lactic acid bacterium, on the intestinal flora of weanling piglets and cows reared on antibiotic-containing diet was investigated. Fourteen days after administration of the bacteria, the intestinal flora of the piglets was examined. Animals of the administered group had stabilized lactic flora such as bifidobacteria, streptococci, and lactobacilli, whereas most animals of control group had reduced lactic flora. On the other hand, abundant yeasts were detected from the cecum, colon, and feces of the control animals, but the levels were significantly lower in the animals given strain BIO-4R. The density of Salmonella in the intestine appeared to be reduced after the administration of strain BIO-4R. The number of BIO-4R cells was shown to be 10 times lower in the duodenum and jejunum than in the ileum, suggesting that strain BIO-4R might have grown transiently in the ileum. The similar trend toward stabilization of the lactic flora was also observed in cows after administration of BIO-4R. In addition, an antagonistic effect of the strain against yeasts and Salmonella was suggested. These findings indicate that the oral administration of strain BIO-4R is one of the useful methods whereby the potentially deleterious effect of antibiotics on the intestinal flora of farm animals may be minimized.     

Hydropiperoside,a novel coumaryl glycoside from the root of Polygonum hydropiper

From the methanol extract of the root of Polygonum hydropiper, a novel coumaryl glycoside hydropiperoside was isolated together with anthraquinone, ellagic acid 3,3′-di-O-methyl ether, gallic acid, two quercetin glycosides and an unidentified aromatic δ-lactone possessing antifertility activity. The structure of hydropiperoside was established as β-d-(1,3,6-tri-p-coumaryl)-fructofuranosyl-α-d-glucopyranoside by combination of extensive ¹H NMR and ¹³C NMR spectra, and the FD/MS spectrum.