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We report results of a high resolution search for the tensor glueball candidate ξ(2230) in a p̄pformation experiment. π0π0and ηηdecay channels were measured in a scan of the mass region 2220 MeV to 2240 MeV. No evidence for the existence of ξ(2230) was found. 95% confidence upper limits for the possible existence of ξare presented.

A combined analysis is reported of 3π0, π0ηand π0η′ data in the mass range 1960 to 2410 MeV. This analysis is made consistent also with ηηπ0data, reported separately. The analysis requires s-channel resonances with a spectrum close to that published earlier for C=+1 states with I=0; masses for I=1 states are lower on average by 20 MeV. Two alternative solutions are found, differing only for JP=2+and 4+states by small amounts in masses and widths. Both 3π0and ηπ0data prefer one of these two solutions. For this preferred solution, observed states have JPC, masses and widths (M,Γ) in MeV as follows: 4−+: (2250±15, 215±25), 4++: (2255±40, 330+110−50) and (2005+25−45, 180±30), 3++: (2275±35, 350+100−50) and (2031±12, 150±18), 2−+: (2245±60, 320+100−40) and (2005±15, 200±40), 2++: (2255±20, 230±15), (2175±40, 310+90−45) and (2030±20, 205±30), and 1++: (2270+55−40, 305+70−35). There are indications of further 2−+, 2++and 1++contributions just below the available mass range, and also a 0++state at ∼2025 MeV.

A partial wave analysis of p̄p→ηηπ0data from the Crystal Barrel experiment is made in terms of s-channel resonances. The decay channels a0(980)η, f0(1770)πand f0(2105)πprovide evidence for two I=1, JPC=0−+resonances. The first has mass M=2360±25 MeV and width Γ=300+100−50 MeV, and the second M=2070±35 MeV, Γ=310+100−50 MeV. There is also evidence for a JPC=2−+state with M=2005±15 MeV and Γ=200±40 MeV, decaying strongly to a0(980)π.

The allosteric enhancer PD 81,723, a 2-amino-3-benzoylthiophene derivative, has been shown to potentiate agonist binding to A1adenosine receptors (A1AdoRs) and to enhance the functional effects of adenosine and adenosine analogs. The objective of this study was to determine whether the apparent agonist-independent effect of PD 81,723 observed in CHO cells stably expressing the recombinant human A1AdoR was due to the potentiation of the action of endogenous adenosine, to the presence of constitutive receptor activity and/or to the binding of PD 81,723 to the agonist binding site of the A1AdoR. The allosteric enhancer PD 81,723, the A1AdoR agonist (R)-N6-(2-phenylisopropyl)adenosine and adenosine all significantly inhibited forskolin-stimulated cAMP accumulation in intact cells and increased [35S]-5′-(γ-thio)triphosphate binding to cell membranes. The effects of adenosine on cAMP formation and [35S]-5′-(γ-thio)triphosphate binding were attenuated by adenosine deaminase, but the effects of PD 81,723 were not. In the presence of ADA, the A1AdoR antagonist 8-cyclopentyl-1,3-dipropylxanthine increased forskolin-stimulated cAMP accumulation in cells expressing the recombinant human A1AdoR but not in nontransfected CHO cells. In binding experiments, the agonist (R)-N6-(2-phenylisopropyl)adenosine, but not PD 81,723, significantly displaced the specific binding of the A1AdoR agonist [3H]-N6-cyclohexyladenosine and the antagonist [3H]-8-cyclopentyl-1,3-dipropylxanthine. The results of this study demonstrate that in CHO cells stably expressing the recombinant human A1AdoR, the agonist-independent effect of PD 81,723 is not due to potentiation of the action of endogenous adenosine or mediated by the binding of the allosteric enhancer to the agonist binding site of the recombinant human A1AdoR. It is possible that these effects are due to potentiation of constitutive receptor activity by PD 81,723.

A soluble, secreted UDP-GalNAc:polypeptide, N-acetylgalactosaminyltransferase, was prepared by substituting the honeybee melittin leader sequence for the sequences coding for the cytoplasmic and membrane spanning domains of a cloned, bovine full-length cDNA (F. L. Homa et al., 1993, J. Biol. Chem. 268, 12609-12616). When this construct was expressed in insect cells using a recombinant baculovirus, a fully active soluble enzyme was recovered from the culture medium. In large-scale preparations, approximately 2-3 mg of enzyme protein was produced per liter of medium. A one-step purification of the soluble molecule on apomucin-Sepharose yielded an essentially homogenous enzyme preparation. The purified soluble enzyme has a molecular mass of approximately 61 kDa and appears to contain both N- and O-linked oligosaccharides. NH₂-terminal sequencing demonstrated that the melittin leader sequence is cleaved at the predicted site and amino acid analysis gave results in close agreement with the composition predicted by the nucleic acid sequence. The enzymatic properties of the soluble, recombinant molecule are similar to those of the enzymes isolated from bovine colostrum and porcine submaxillary gland: the specific activity is approximately 2160 U/mg protein and the K_ms for UDP-GalNAc and the synthetic acceptor peptides PPASTSAPG and PPDAASAAPLR are approximately 1.7 µM, 6.5 mM, and 3.6 mM, respectively.Copyright 1995, 1999 Academic Press, Inc.

Antenatal sex was correctly identified in 87.5% of the rhesus monkeys studied by evaluation of sex chromatin bodies in the exfoliated cells present in amniotic fluid. Fluid samples were obtained by either amniocentesis, amnioscopy, or by cesarean section at 80–120 days of gestation. Amniotic fluid concentrations of progesterone, total estrogen, and testosterone were not correlated with fetal sex. Concentrations of these hormones decreased over the time period examined. Amniocentesis is a simple procedure which provides for routine fetal sex determination.

Abstract: Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko), is an important pest of wheat (Triticum aestivum L.) in the United States of America. Developing adapted wheat cultivars with genetic resistance to RWA is an effective control strategy. Genetic studies were conducted to determine the mode of inheritance of gene(s) conferring resistance to RWA in an Iranian landrace wheat line, G 5864. For the inheritance study, G 5864 was crossed with the susceptible wheats ‘Yecora Rojo’ and ND 2375. Seedlings of F1, reciprocal F1, F2, BC1 to the susceptible parent (BCS), and BC1 to the resistant parent (BCR) were screened for RWA reaction. Several phenotypic segregation ratios were tested in the F2 populations for goodness of fit; the 9:3:3:1 ratio (resistant: rolled leaves: stunted plants: susceptible) was an acceptable fit in all cases. Thus, resistance in G 5864 seemed to be controlled by two independent dominant genes with additive gene effects. The allelic relationships of gene(s) in this line with genes in other resistant lines, PI 137739 (Dn1), PI 262660 (Dn2), PI 372129 (Dn4), PI 294994 (Dn5), and PI 243781 (Dn6), were also studied. Segregation patterns observed in G 5864 × resistant (R × R) F2 populations were inconclusive. However, no susceptible plants were observed in these F2 populations. If previous reports concerning the number of resistance genes present in the other resistant lines are correct, then given the high manifestation of resistance observed in G 5864, and given the absence of susceptible plants in the R × R F2 populations, it is indicated that RWA resistance in G 5864 is either controlled by different alleles at the same loci as the other resistance genes, or that G 5864 shares a resistance gene with each of the other resistant lines.

A rapid and simple method for quantitating the reaction product of UDP-GalNAc:polypeptide,N-acetylgalactosaminyltransferase (GalNAc-transferase) by scintillation proximity assay (SPA) was developed. The assay quantitates the radioactivity incorporated from3H-labeled UDP-GalNAc into a biotin-labeled acceptor peptide, as measured after adsorption of the acceptor peptide to avidin-coated SPA beads. The acceptor peptide, PPASTSAPG (Elhammeret al.(1993)J. Biol. Chem.268, 10029–10038) was conjugated to biotin using a di-β-alanine spacer arm. The conjugated peptide reacted readily with the enzyme and it had an apparentKmcomparable to that of the parent peptide. Using a reaction mixture consisting of 4 mg of SPA beads, 17 μMacceptor, 0.5 μMnucleotide sugar, and 7.5 U/ml enzyme, the time dependence of product formation obeyed Michaelis–Menten-type kinetics throughout the full course of the reaction—until exhaustion of the donor substrate—and the beginning portion of the reaction was sufficiently linear for calculating accurate initial rates. Analysis of the time dependency yielded an apparentKmof 0.38 ± 0.12 μMfor UDP-GalNAc. The assay is conveniently carried out in 96-well microtiter plates; it is ideally suited for assaying large numbers of samples and for screening large collections of chemicals for competitive inhibitors.