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Experiments using high-efficiency neutron detectors have detected neutron emission from various forms of Pd and Ti metal in pressurized D2 gas cells and D2O electrolysis cells. Four independent neutron detectors based on3He gas tubes were used. Both random neutrons (0.05–0.2 n/s) and time-correlated neutron bursts (10–280 n) of =100-µs duration were measured using time-correlation counting techniques. The majority of the neutron burst events occurred at ~ -30°C as the samples were warming up from the liquid nitrogen temperature.

An orphan receptor discovered in 1993 was called bombesin receptor subtype 3 (BRS-3) because of 47-51% amino acid identity with bombesin (Bn) receptors. Its pharmacology is unknown, because no naturally occurring tissues have sufficient receptors to allow studies. We made two cell lines stably expressing the human BRS-3 (hBRS-3). hBRS-3 was overexpressed in the human non-small cell lung cancer cells, NCI-H1299, and the other was made in Balb 3T3 cells, which lack endogenous BRS-3. [D-Phe6,beta-Ala11,Phe13, Nle14]Bn-(6-14) (where Nle represents norleucine) was discovered to have high potency for stimulating inositol phosphate formation in both cell lines. [125I-D-Tyr6,beta-Ala11,Phe13, Nle14]Bn-(6-14) bound to both cell lines with high affinity. Neither Bn nor 14 other naturally occurring Bn peptides bound to hBRS-3 with a Kd <1000 nM. Twenty-six synthetic peptides that are high affinity agonists or antagonists at other bombesin receptors had an affinity >1000 nM. Guanosine 5'-(beta,gamma-imido)triphosphate inhibited binding to both cells due to a change in receptor affinity. These results demonstrate hBRS-3 has a unique pharmacology. It does not interact with high affinity with any known natural agonist or high affinity antagonist of the Bn receptor family, suggesting the natural ligand is either an undiscovered member of the Bn peptide family or an unrelated peptide. The availability of these cell lines and the hBRS-3 ligand should facilitate identification of the natural ligand for BRS-3, its pharmacology, and cell biology.

The extraction of Am(III) and Eu(III) from aqueous HCIO4 by BMPPT and TOPO in benzene was studied. The ligand BMPPT gave no detectable extraction in the ranges studied, but when BMPPT and TOPO were combined, a synergistic extraction was observed with a selectivity for Ara(III) over Eu(III) (KdAm = 7.5, Am/Eu = 68, pH 3.0, 0.01 M [TOPO], 0.30 M [BMPPT]). The slope of the acid dependency for Eu and Am was 1.6 ± 0.1 and 2.7 ± 0.1, respectively, over the pH range of 2 to 3.The slope of the BMPPT dependency was 2.7 ± 0.1 and 2.8 ± 0.1 over a 2- and 20-fold concentration range for Eu and Am, respectively; the slope of the TOPO dependency was 2.0 ± 0.1 and 2.2 ± 0.1 for Am and Eu, respectively, over a 20-fold concentration range.

Bombesin (Bn) receptor subtype 3 (BRS-3) is an orphan receptor that is a predicted member of the heptahelical G-protein receptor family and so named because it shares a 50% amino acid homology with receptors for the mammalian bombesin-like peptides neuromedin B (NMB) and gastrin-releasing peptide. In a recent targeted disruption study, in which BRS-3-deficient mice were generated, the mice developed obesity, diabetes, and hypertension. To date, BRS-3's natural ligand remains unknown, its pharmacology unclear, and cellular basis of action undetermined. Furthermore, there are few tissues or cell lines found that express sufficient levels of BRS-3 protein for study. To define the intracellular signaling properties of BRS-3, we examined the ability of [D-Phe6,beta-Ala11,Phe13, Nle14]Bn-(6-14), a newly discovered peptide with high affinity for BRS-3, and various Bn receptor agonists and antagonists to alter cellular function in hBRS-3-transfected BALB 3T3 cells and hBRS-3-transfected NCI-H1299 non-small cell lung cancer cells, which natively express very low levels of hBRS-3. This ligand stimulated a 4-9-fold increase in [3H]inositol phosphate formation in both cell lines under conditions where it caused no stimulation in untransfected cells and also stimulated an increase in [3H]IP1, [3H]IP2, and 3H]IP3. The elevation of [3H]IP was concentration-dependent, with an EC50 of 20-35 nM in both cell lines. [D-Phe6,beta-Ala11,Phe13,Nle14]Bn-(6-14) stimulated a 2-3-fold increase in [Ca2+]i, a 3-fold increase in tyrosine phosphorylation of p125(FAK) with an EC50 of 0.2-0.7 nM, but failed to either stimulate increases in cyclic AMP or inhibit forskolin-stimulated increases. None of nine naturally occurring Bn peptides or three synthetic Bn analogues reported to activate hBRS-3 did so with high affinity. No high affinity Bn receptor antagonists had high affinity for the hBRS-3 receptor, although two low affinity antagonists for gastrin-releasing peptide and NMB receptors, [D-Arg1,D-Trp7,9, Leu11]substance P and [D-Pro4,D-Trp7,9,10]substance P-(4-11), inhibited hBRS-3 receptor activation. The NMB receptor-specific antagonist D-Nal,Cys,Tyr,D-Trp,Lys,Val, Cys,Nal-NH2 inhibited hBRS-3 receptor activation in a competitive fashion (Ki = 0.5 microM). Stimulation of p125(FAK) tyrosine phosphorylation by hBRS-3 activation was not inhibited by the protein kinase C inhibitor, GF109203X, or thapsigargin, alone or in combination. These results show that hBRS-3 receptor activation increases phospholipase C activity, which causes generation of inositol phosphates and changes in [Ca2+]i and is also coupled to tyrosine kinase activation, but is not coupled to adenylate cyclase activation or inhibition. hBRS-3 receptor activation results in tyrosine phosphorylation of p125(FAK), and it is not dependent on activation of either limb of the phospholipase C cascade. Although the natural ligand is not a known bombesin-related peptide, the availability of [D-Phe6,beta-Ala11, Phe13,Nle14]Bn-(6-14), which functions as a high affinity agonist in conjunction with hBRS-3-transfected cell lines and the recognition of three classes of receptor antagonists including one with affinity of 0.5 microM, should provide important tools to assist in the identification of its natural ligand, the development of more potent selective receptor antagonists and agonists, and further exploration of the signaling properties of the hBRS-3 receptor.

This first single crystal study of the heavy‐fermion superconductor UBe13shows the compound to crystallize in the cubic system (Fm3c, Z = 8).

The title compounds (I), prepared by published methods, are characterized in view of the Gd complex (Ia) as a magnetic resonance imaging contrast agent.

Studies show that the fate of H2addition to the unsaturated, air‐sensitive 16‐electron precursors (III), obtained according to the scheme, rests primarily on the basicity of the metal center as dictated by the electron‐donating ability of the ancillary phosphine ligands.

The initially formed SO2adduct (III) further reacts with SO2with formation of the thiosulfato complex (IV).

The bifunctional (sulfonylmethyl)phosphonates (IV) and (VIII), and the (sulfinylmethyl)phosphonate (V) are synthesized according to the scheme and characterized spectroscopically (IR, 1H, 13C, 31P NMR).

Uranyl nitrate (II) and the ligand (Ia) react in EtOH to give the complex (IIIa).

The title complex is obtained by treating of U(BH4)3·nTHF in THF with a toluene solution of (η5‐C5Me5)2Th(PPh2)2 containing NaCl and characterized by X‐ray structure analysis (space group P1, Z=2).

The results of an electron diffraction study at ‐42 °C confirm the O2F2molecule to have C2 symmetry, with a short O‐O bond and extraordinarily long O‐F bonds.

The structures of the title complexes (III) and (V) are determined by X‐ray analysis.

The preparation of the ligand compounds (III) is shown in the scheme.

Tl trichloride and in situ generated K(HFe(CO)4) react to form K(Tl(Fe(CO)4)2).

The structure of the title complex (I) is determined by X‐ray diffraction (space group P21/n, Z=4).