Bis(di-2-pyridylmethane-diol-κN,O,N')copper(II) dl-tartrate.

The reaction of di-2-pyridyl ketone with copper dichloride dihydrate and tartaric acid in water afforded the title compound, [Cu(C(11)H(10)N(2)O(2))(2)]C(4)H(4)O(6). The Cu(II) atom lies on an inversion center N,O,N'-chelated by two di-2-pyridylmethane-diol ligands in a tetragonally distorted octa-hedral geometry. The tartrate anion is also located on an inversion center and has disordered hydroxyl groups, each with an occupancy factor of 0.

catena-Poly[[tetra-aqua-(μ-4,4'-bipyridine-κN:N')zinc(II)] fumarate tetra-hydrate].

In the title compound, {[Zn(C(10)H(8)N(2))(H(2)O)(4)](C(4)H(2)O(4))·4H(2)O}(n), the Zn(II) atom is coordinated by two N atoms from two μ-4,4'-bipyridine ligands and four water mol-ecules in a distorted octa-hedral geometry. The coordination unit is extended through the Zn-N bond, leading to a one-dimensional cationic chain. A twofold rotation axis passes through the Zn atom and along the axis of the 4,4'-bipyridine ligand.

An investigation of the self-assembly of neutral, interlaced, triple-stranded molecular braids.

The synthesis and structures of six compounds prepared in two different systems have been explored with the purpose of isolating coordination polymers with interlaced triple-stranded molecular braid architectures. The dinuclear paddle-wheel units of [Cu(2)(maa)(4)2 H(2)O] can be rationally tuned to form three classes of isomorphous compounds, namely [Cu(2)(maa)(4)(bpp)] (1) (bpp=1,3-bis(4-pyridyl)propane, Hmaa=2-methylacrylic acid), [Cu(3)(maa)(6)(bpp)(2)] (2), and[Cu(4)(maa)(8)(bpp)(4)(H(2)O)(2)]2 H(2)O (3), with a bridging bpp ligand, at controlled ligand-to-metal molar ratios, and lead to three coordination polymers having similar one-dimensional characteristics but different mono- and dinuclear nodes. Compound 1, with a bpp:[Cu(2)(maa)(4)2 H(2)O] stoichiometry of 1:1, contains a zigzag chain containing dinuclear nodes, whereas polymer 2, with a bpp:[Cu(2)(maa)(4)2 H(2)O] stoichiometry of 1.

Influence of polarized bias and porous silicon morphology on the electrical behavior of Au-porous silicon contacts.

This paper reports the surface morphology and I-V curves of porous silicon (PS) samples and related devices. The observed fabrics on the PS surface were found to affect the electrical property of PS devices. When the devices were operated under different external bias (10 V or 3 V) for 10 min, their observed obvious differences in electrical properties may be due to the different control mechanisms in the Al/PS interface and PS matrix morphology.

A novel high molecular weight metalloproteinase cleaves fragment F1 of activated human prothrombin.

A hemorrhagic proteinase, jerdohagin, was purified from Trimeresurus jerdonii venom by gel filtration and ion-exchange chromatographies. It was a single chain polypeptide with an apparent molecular weight of 96 kDa as estimated by SDS-PAGE under the non-reducing and reducing conditions. Internal peptide sequencing indicated that it consisted of metalloproteinase, disintegrin-like and cysteine-rich domains and belonged to the class III snake venom metalloproteinases (class P-III SVMPs).

Purification, characterization and primary structure of a chymotrypsin inhibitor from Naja atra venom.

A chymotrypsin inhibitor, designated NA-CI, was isolated from the venom of the Chinese cobra Naja atra by three-step chromatography. It inhibited bovine alpha-chymotrypsin with a Ki of 25 nM. The molecular mass of NA-CI was determined to be 6403.

[The effects of neuropeptides on the regulations of gastric mucosal blood flow in central nervous system and periphery in rats].

Aim: To investigate the effects of calcitonin gene-related peptide (CGRP), gastrin 17 (G17), bombesin (Bom), met-enkephalin (Met-enk), neuropeptide Y (NPY) and somatostatin (SS) on GMBF and the role of endogenous NO in increased GMBF induced by neuropeptides in rats.

Methods: By hydrogen gas clearance technique to measure gastric mucosal blood flow (GMBF) and arterial infusion close to stomach or intracerebroventricular (icv) to microinject neuropeptides.

Results: (1) Arterial infusions of CGRP and G17 (5, 50 and 100 pmol x min(-1)) increased GMBF significantly in dose-dependent manners.

Jerdonase, a novel serine protease with kinin-releasing and fibrinogenolytic activity from Trimeresurus jerdonii venom.

A novel kinin-releasing and fibrin(ogen)olytic enzyme termed jerdonase was purified to homogeneity from the venom of Trimeresurus jerdonii by DEAE Sephadex A-50 anion exchange, Sephadex G-100 (superfine) gel filtration and reverse-phase high performance liquid chromatography (RP-HPLC). Jerdonase migrated as a single band with an approximate molecular weight of 55 kD under the reduced conditions and 53 kD under the non-reduced conditions. The enzyme was a glycoprotein containing 35.

Alpha-neurotoxins of Naja atra and Naja kaouthia snakes in different regions.

Recent studies have shown that there are geographic variation of alpha-neurotoxins in Naja kaouthia, but the cause is not clear yet. In this work, venoms were collected from adult Naja atra in Zhejiang Province and Naja kaouthia in Yunnan Province, well identified by morphological characters and cytochrome b gene analysis in summer season to avoid age and seasonal variation in the venom composition. Then alpha-neurotoxins were purified and cloned from these two kinds of snakes.

Characterization of a new bradykinin-potentiating peptide (TmF) from Trimeresurus mucrosquamatus.

A novel bradykinin-potentiating peptide (BPP), designated as TmF, has been purified to homogeneity from the venom of Trimeresurus mucrosquamatus by 70% cold methanol extraction, Sephadex G-15 gel filtration and reverse-phase high performance liquid chromatography (RP-HPLC). The amino acid sequence of TmF was determined to be pGlu-Gly-Arg-Pro-Leu-Gly-Pro-Pro-Ile-Pro-Pro (pGlu denotes pyroglutamic acid), which shared high homology with other BPPs. The molecular mass of TmF was 1.

[Capsaicin-sensitive afferent fibers and endogenous NO mediate the gastric acid secretion and gastric mucosal blood flow in intragastric distention in rats].

Aim And Methods: By hydrogen gas clearance technique to measure gastric mucosal blood flow (GMBF) and a high dose of capsaicin to ablate the capsaicin-sensitive afferent fibers, the roles of capsaicin-sensitive afferent fibers and endogenous NO in the gastric acid secretion and hyperemic response to intragastric distention were studied in rats.

Results: (1) There was an increase in acid secretion associated with the increase in GMBF to intragastric distention. (2) Pretreatment with a high dose of capsaicin to ablate afferent fibers completely abolished the GMBF and partially inhibited the acid secretion during the intragastric distention.

Characterization and cloning of a novel phospholipase A(2) from the venom of Trimeresurus jerdonii snake.

A phospholipase A(2) (PLA(2)), called jerdoxin, was isolated from Trimeresurus jerdonni snake venom and partially characterized. The protein was purified by three chromatographic steps. SDS-polyacrylamide gel electrophoresis in the presence or absence of dithiothreitol showed that it had a molecular mass of 15 kDa.