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By copolymerizing a thermosensitive primary component, N‐isopropylacrylamide (NIPA), and an ionic secondary component, 2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid (AMPS) between two substrates of hydrophilic glass and hydrophobic polytetrafluoroethylene (Teflon), a novel composition‐gradient copolymer gel, in which the AMPS content decreases gradually towards Teflon, is prepared. The formation of the composition‐gradient in NIPA‐co‐AMPS gels is discussed in terms of the work of adhesion between a solution and a substrate, i.e., the liquid‐solid interfacial free energy. The work of adhesion is determined from the Young‐Dupré equation on the basis of the measured contact angle and the surface tension in the system consisting of an aqueous solution containing NIPA or AMPS monomers or polymers and glass or Teflon as the substrate. The values of the work of adhesion of AMPS monomer and polymer on Teflon were lower than those on glass. Thus, AMPS remains relatively stable at the glass interface and unstable at the Teflon interface. This repulsion of AMPS due to the hydrophobicity of the Teflon wall generates the composition‐gradient.

A stereocontrolled total synthesis of (−)-kainic acid is described. cis-3,4-Disubstituted pyrrolidine ring was constructed by [3 + 2] cycloaddition of azomethine ylide with chiral butenolide. The crucial introduction of carboxyl group at the C-2 position was executed by regio- and stereoselective lithiation of the pyrrolidine ring in the presence of a (+)-sparteine surrogate followed by trapping with carbon dioxide.

A mild intermolecular copper-mediated amination of aryl iodides has been developed. The reaction takes place at room temperature or heating at 90 °C and tolerates halogens attached to the aromatic ring. Its synthetic applications include a synthetic protocol for unsymmetrical N,N‘-dialkylated phenylenediamines and both a stepwise and a general synthetic method for N-aryl secondary amines via Ns-anilides (readily obtained by reaction of the Ns-amide).

Stereocontrolled total synthesis of (+)-vinblastine (1) has been achieved using a novel radical-mediated indole synthesis developed in our laboratories. The isothiocyanate 18, prepared readily from quinoline 17, underwent a facile addition of the malonate anion to give 19. The o-alkenylthioanilide 19was then converted to indole 20by radical cyclization and protection. (−)-Vindoline (2) was prepared from this key intermediate 20in a highly efficient manner. The indole core of the 11-membered intermediate 3was constructed similarly from quinoline. The critical coupling reaction between 2 and the chloroindolenine derived from 3proceeded with complete control of stereochemistry to give the desired product 66in 97 % yield, which could be successfully converted to (+)-vinblastine (1).

An ion-exchange experiment with a countercurrent multistage fluidized bed has been carried out. The nitrate ion was effectively removed from a dilute nitric acid solution by anion-exchange resins. The outlet concentration, Cout, coincides well with the one simulated on the basis of the ion-exchange equilibrium and the effective diffusivity, De, within the resin particle. The ion-exchange equilibrium of DIAION SA10A or WA10 with a HNO3 solution in the batch experiment is expressed by the Freundlich isotherm. The value of De measured with a fixed bed for ion exchange between an anion-exchange resin and a HNO3 solution was 1 × 10^-12 m²/s for SA10A and 1.5 × 10^-12 m²/s for WA10, respectively. Calculation of a multistage fluidized bed has shown that the removal of HNO3 is promoted with increasing stage number and increasing resin flow rate, while it decreases with increasing liquid flow rate. An increase in the stage number increases not only the removal fraction but also the ion loading of the resin.

AbstractAims: The role of cyclooxygenase (COX)-1/2-induced prostaglandins (PG) in unilateral chronic renal ischemia of anesthetized dogs was examined. Methods: Ischemic kidneys were established by reducing renal blood flow of left renal artery to 10% of baseline with an adjustable clip. After 4 weeks, changes in intrarenal contents of PGE2/PGI2 and angiotensin (Ang) II were evaluated with renal microdialysis and biopsy. Furthermore, the effect of a non-specific COX inhibitor (sulpyrine), a COX-2-specific inhibitor (NS398), and an Ang receptor antagonist (CS866) on renal function and renal PG contents were evaluated. Results: Unilateral renal artery clipping reduced renal plasma flow (RPF) in clipped (from 59 ± 2 to 17 ± 1 ml/min, n = 18) and nonclipped kidneys (from 59 ± 2 to 44 ± 2 ml/min) and natriuresis. Intrarenal PGE2 increased only in clipped kidneys (from 114 ± 7 to 375 ± 25 pg/ml), whereas 6-keto-PGF1α increased in both kidneys. Sulpyrine reduced intrarenal PG contents, and decreased RPF, GFR, and urinary sodium excretion (UNaV), whereas NS398 reduced UNaV in clipped (from 4.0 ± 0.9 to 1.7 ± 0.2 μEq/min) and nonclipped kidneys (from 5.4 ± 0.5 to 2.9 ± 0.3 μEq/min), without affecting renal hemodynamics. Intrarenal Ang II contents increased in clipped (from 0.70 ± 0.06 to 2.32 ± 0.33 pg/mg, n = 18) and nonclipped kidneys (from 0.65 ± 0.06 to 2.45 ± 0.33 pg/mg, n = 18), and CS866 improved renal hemodynamics and natriuresis. The elevated intrarenal Ang II content was suppressed by NS398 only in clipped kidneys. Conclusion: Unilateral renal ischemia elevates intrarenal PGE2 contents in clipped kidneys, which serves to countervail the aggravation of renal function. Furthermore, intrarenal COX isoforms may play differential roles, with COX-1 participating in modulation of renal hemodynamics, and COX-2 contributing to sodium excretion and Ang II formation.Copyright © 2002 S. Karger AG, Basel

Abstract: Background. Although glucocorticoids elicit systemic hypertension, they are also demonstrated to cause marked increases in renal blood flow. The mechanism of this alteration, however, remains undetermined. Methods. Dogs were treated with dexamethasone (DEX) for 7 days, and renal, as well as systemic hemodynamic, responses to DEX were assessed. In addition, the role of intrarenal angiotensin (ANG) II in mediating the glucocorticoid-induced renal vasodilation was examined in conscious unrestrained dogs. Results. Seven-day treatment with DEX caused prominent increases in mean arterial pressure (MAP; from 80 ± 2 to 98 ± 5 mmHg) and in renal plasma flow (RPF; from 142 ± 4 to 191 ± 7 ml/min), with decreases in renal vascular resistance [RVR; from 0.26 ± 0.01 to 0.22 ± 0.01 mmHg/(ml/min)] and in the filtration fraction (FF; from 0.24 ± 0.01 to 0.20 ± 0.01). DEX treatment did not alter plasma ANG II levels, but enhanced candesartan-induced reduction in MAP. In contrast, the candesartan-induced increase in RPF (19 ± 2% increase) was completely abolished by DEX. DEX treatment markedly reduced renal tissue ANG II content (from 1.09 ± 0.07 to 0.71 ± 0.04 pg/mg tissue), which paralleled the response of renal tissue angiotensin-converting enzyme (ACE) activity (−20 ± 4%). Finally, intravenous ANG II administration caused a greater reduction in RPF during the DEX treatment period (−17 ± 2% vs −11 ± 1% in the control period). Conclusions. Glucocorticoids cause hypertension, but they also cause a paradoxical decrease in RVR and increase in RPF. The renal responses to candesartan and exogenous ANG II during DEX treatment suggest that the attenuation of intrarenal ANG-mediated vascular tone plays an important role in the altered renal hemodynamics. The decreased ANG tone is likely caused by reduced ANG II formation, resulting in part from suppressed ACE activity, but not from decreased sensitivity to ANG II.

Enantioselective synthesis of FR-900482 analogues is described. The key reaction of the synthesis is intramolecular 1,3-dipolar cycloaddition of a highly functionalized nitrile oxide with complete stereo- and regioselectivities to construct the eight-membered benzazocine ring.

A comparative study of the present collision zone between the Izu-Bonin Ridge (island arc) with mainland Japan (Honshu Arc), and the Mio-Pliocene of onshore SE Japan, suggests that arc-arc collision processes and the resulting stratigraphic successions may be repetitious and predictable. Arc-arc collision has led to the incremental accretion of segments of delaminated Izu-Bonin Arc crust onto the Honshu Arc, associated with the sequential southward migration in jumps of the plate boundary and trench. Prior to accretion of a segment of Izu-Bonin Arc crust, the leading edge underwent uplift to generate an approximately trench-parallel topographic high, the Zenisu Ridge being the present example with the Hayama-Mineoka uplift zone as a Mio-Pliocene example. The ridge separated a northern trench or trough from a southern intra-oceanic arc basin. During collision-accretion, the trench received both Honshu Arc-derived, terrigenous, and Izu-Bonin Arc-derived volcaniclastic, sediments, whereas the arc basin tended to receive only arc deposits. During the final stages of accretion, the arc basin began to receive ever-increasing volumes of terrigenous, Honshu Arc-derived, detritus fed through basement-controlled canyons. The accretionary process was accompanied by intense deformation and the residual deep-marine basin was then infilled above an angular unconformity.

“Monthly Planning System of Production Activities of Kashima Steel Works” has been developed and is contributing greatly to the operation of the steelworks and to the reduction of the production cost. This system consists of four subsystems, i.e., the maintenance planning system, the production planning system, the energy planning system, and the data linkage system, the former three supporting the corresponding planning, and the last administering the communication among them.

Defatted bovine colostrum and decaseinated whey contain biological activity similar to that of TGF-β in that they stimulate the anchorage-independent growth of NRK-49F cells in the presence of EGF. Two new proteins with such activity, termed BC-1 and BC-2, were isolated from decaseinated colostrum by a sequence of DEAE-Sephacel chromatography, Sephadex G-100 gel filtration in 1 M acetic acid, Sephadex G-50 re-gelfiltration in 8 M urea-1 M acetic acid and reverse-phase FPLCs. The two proteins showed distinctly different molecular weight from that of TGF-β1. BC-1 was a small Mr peptide of 8.5 kD. BC-2 had molecular mass of 46 kD, which yielded peptides of 46, 40, and 6 kD on reduction. In contrast to TGF-β, both proteins did not lose their biological activity on reduction. Both BC-1 and BC-2 suppress DNA synthesis in concanavalin A-stimulated thymocytes. These results suggest that BC-1 and BC-2 belong to a new class of mitogen/inhibitors, though their biological activities resemble those of TGF-β.

Substituted cyclopentadienone acetals (CPDAs) were synthesized by a thermal or palladium-catalyzed [3 + 2] cycloaddition reaction of a substituted cyclopropenone acetal to an electron-deficient acetylene. The synthesis afforded di-, tri-, and tetrasubstituted CPDAs of considerable structural varieties that undergo Diels−Alder reaction to produce bicyclo[2.2.1]heptenes.

An enantioselective total synthesis of aspidophytine is described. The indole fragment bearing a cis-alkene substituent was efficiently prepared through radical cyclization of a 2-alkenylphenylisocyanide followed by Sonogashira coupling of the generated 2-iodoindole derivative with a functionalized acetylene unit. After formation of the 11-membered cyclic amine, the aspidosperma skeleton and lactone ring were constructed to complete the total synthesis.

A novel fluorescent reagent for hydroperoxides, 4-(2-diphenylphosphinoethylamino)-7-nitro-2,1,3-benzoxadiazole (1), was developed on the basis of the method for designing photoinduced electron transfer (PET) reagents having a benzofurazan skeleton. Compound 1 was quantitatively reacted with hydroperoxides to give its fluorescent derivative, 2. In acetonitrile, the Φ value (0.44) of 2 was 31 times greater than that of 1. The long excitation (458 nm) and emission (520 nm) wavelengths of 2 are suitable for the determination of hydroperoxides, especially in biosamples.

Leg 61 of the Deep Sea Drilling Project (DSDP) was concerned with drilling a single continuously cored multiple re-entry hole at site 462 in the Central Nauru Basin (Fig. 1). Preliminary results of this drilling, which penetrated more than 1 km beneath the sea floor, were presented earlier1,2. One major result was the discovery of a late Cretaceous off-ridge volcanic/intrusive complex of basaltic composition and great thickness (>500 m). We now present trace element abundance data for these basalts. Results of the drilling provide further support for a relatively long-lived thermal and magmatic event in the late Cretaceous resulting in voluminous and widespread magmatism in the central and western Pacific consistent with earlier suggestions3–5. The trace element data show that most of the rocks produced during this event have trace element characteristics intermediate between those of normal and transitional mid-ocean ridge basalts (N- and T-type MORB)6and different from Hawaiian basalts7. These results indicate that basalts which are depleted in light rare earth elements (LREE) relative to the heavy REE may, in certain conditions, be erupted as voluminous intra-plate eruptions far from active ridge crests.

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