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Abstract: An efficient method to prepare ABAC-type oxacalix[4]arenes by a ‘3+1’ fragment synthesis and their CsF-catalyzed disproportionation producing an equilibrium mixture of three oxacalix[4]arenes are described. [Copyright &y& Elsevier]

Methylene-bridged resorcin[4]arene dimers were synthesized by the Sc(OTf)3-catalyzed hydroxymethylation of partially acetylated resorcin[4]arenes, and their preliminary complexation properties with tetraethylammonium ion were examined in CD3OD by1H NMR spectroscopy. The dimers adopted a closed capsular conformation in this solvent and bound the guest molecule into their cavity. [ABSTRACT FROM AUTHOR]

Abstract: Tetranitroazacalix[4]arenes have been synthesized by the nucleophilic aromatic substitution of 1,5-difluoro-2,4-dinitrobenzene with 1,3-diaminobenzenes. An X-ray crystal structure analysis revealed that the azacalixarenes adopt a non-symmetrical 1,3-alternate conformation, and the dinitrobenzene rings strongly conjugate with the bridging nitrogen atoms. In the 1H NMR spectrum (CDCl3, 30°C), the tetraisopropyl derivative 3b displays a pair of diastereotopic methyl signals of the isopropyl groups in agreement with the frozen 1,3-alternate conformation on the NMR time scale. The free energy of activation () for the macrocyclic inversion was determined to be 87.5kJmol−1 by temperature-dependent NMR spectroscopy. [Copyright &y& Elsevier]

Abstract: The thermal isomerization of anti to syn stereoisomers of oxacalix[4]arene bearing two methyl groups at the intra-annular distal positions was investigated by temperature-dependent NMR spectroscopy. The conversion followed a first-order kinetics, and very slowly proceeded at 473K in nitrobenzene-d 5 with a half-life of 7.2h. The free energy of activation (ΔG ≠ 139kJmol−1) is much higher than those for the ring inversion of related calix[4]arene derivatives. [Copyright &y& Elsevier]

Abstract: A facile synthetic method for 4,5-diaminopyrrolo[1,2-a]quinoline derivatives has been developed. Treatment of 2-(pyrrol-1-yl)benzaldehydes with secondary amine hydrochloride/NaI/TMSCl/Et3N in the presence of an isocyano compound leads to the formation of 4-alkyl(or aryl)amino-5-dialkylaminopyrrolo[1,2-a]quinolines. [Copyright &y& Elsevier]

Assesses the effects of sivelestat, a neutrophil elastase inhibitor, on the production of chemokines from cultured A549 cells, a human AEC-II-like cell line. Information on the cell culture; Details on the dose- and time-response curves for interleukin-8 and monocyte chemoattractant protein-1 secretion from stimulated A549 cells; Conclusion of the study.

Abstract: The nucleophilic aromatic substitution of 1,5-difluoro-2,4-dinitrobenzene with 2-propylresorcinol in Et3N/CH3CN produces a mixture of syn and anti conformers of the cyclic tetramer and the cyclic hexamer with a kinetically controlled product distribution. Moreover, the reaction in DMF was catalyzed by CsF to also produce a mixture of these cyclic oligomers. In this case, however, the C–O bond is cleaved by the fluoride ion and the cyclization reaction is reversible; therefore, in the presence of excess CsF, the thermodynamically favored product (syn-isomer of cyclic tetramer) is obtained as the major product. The structures of the two conformational isomers of cyclic tetramers were determined by X-ray crystallography. [Copyright &y& Elsevier]

2,4-Disubstituted quinolines have been synthesized by reactions of o-isocyano-β-methoxystyrenes, which can be easily prepared from commercially available o-aminophenyl ketones in three steps, with alkyl(or aryl)lithiums in generally good yields. Subsequently, o-isocyano-β-methoxystyrenes have also proved to react efficiently with lithium dialkylamides to afford the corresponding 4-substituted N,N-dialkylquinolin-2-amines in satisfactory yields. [Copyright &y& Elsevier]

Three variants of murine serotonin transporter (5-HTT) mRNA, which consist of a different exon-one (exon 1a, exon 1b or exon 1c) and the same exon-two to exon-five, were identified. The promoter region for each exon 1 (p1a, p1b and p1c, respectively), ligated to pGL-3 enhancer vector, had activities significantly higher than the empty vector in all cell lines tested except p1c in PC-12, whereas the activity of p1c was significantly lower than the others. Effects of the treatment of dibutyryl-cyclic AMP, human interferon-α or mouse interferon-γ have different profiles among COS-7, PC-12, C6 glioma and immortalized rat serotonergic raphe neurons, RN46A. These three promoter regions may play a role in the transcription of the 5-HTT and could offer a model of the regulation of 5-HTT production in humans and further the pathogenesis of depression. [Copyright &y& Elsevier]

The stability of optical beats in a chaotically oscillating laser is compared to that of a free-running continuous-wave laser using a highly efficient plasmonic photomixer. Using a chaotically oscillating laser diode, stable optical beats are observed over an operation current range of 60-90 mA. The optical spectra are stable even with frequent mode hopping. In contrast, optical beats in a free-running continuous-wave laser are not stable compared to those of a chaotically oscillating laser, because of intermittent hopping of the laser modes. The high stability of chaotically oscillating lasers makes these lasers promising candidates for optical pump sources in terahertz time-domain spectroscopy systems.

We propose objectively assessing endoscopic sinus surgery (ESS) skills by measuring the force applied to a patient model. We collected data on 16 subjects performing gauze packing task using a precise human nasal model with a six-degree-of-freedom force/torque sensor. Mann-Whitney's U test was used to analyze their performance. Intermediates (ESS: 10-50 cases) used significantly greater force than students or experts (ESS: over 150 cases) at the 5 % level. Maximum force improved only among experts. These results imply that young surgeons pay too little attention to force applied to patients or tissues.

The purpose of this study was to investigate a suitable occlusal height for an implant prosthesis by examining the responses of the periodontal tissues around a natural antagonist. The subjects were three Japanese females with two posterior missing teeth restored by ITI system implants (Straumann). Two kinds of experimental implant prostheses were adjusted as follows; one was adjusted in heavy clenching (HC), and the other was adjusted in light clenching (LC). The periodontal pulsation, displacement during biting an occlusal force meter and the mobility of the antagonist were measured before and one week after temporary cementing HC and LC, and one week after removal. In each prosthesis, there was no significant difference in the amounts of the pulsation and mobility of the antagonist before and one week after cementing, and one week after removal (p>0.05). The displacement of the antagonist during biting the occlusal force meter did not change much during the conditions. The results of this study suggested that an implant prosthesis adjusted not only under heavy clenching but light clenching like crown restorations for natural teeth did not affect the periodontal tissues of the antagonist in a harmful manner.

The apprenticeship of procedures in endoscopic sinus surgery has several limitations, including potential risk for the patients and lack of feedback to the trainees. In this paper, we present a new surgical training system that combines a head dummy, force and position sensors: this system can be used to assess surgical skills and provide visual feedback to the trainees.

Tumor necrosis factor-alpha (TNF-alpha) is thought to be important in the development of pulmonary fibrosis. However, surfactant protein-C/TNF-alpha transgenic mice do not spontaneously develop pulmonary fibrosis but instead develop alveolar enlargement and loss of elastic recoil. We hypothesized that overexpression of TNF-alpha in the lung requires an additional insult to produce fibrosis. In this study we evaluated whether TNF-alpha overexpression altered the development of pulmonary fibrosis due to bleomycin or transforming growth factor-beta (TGF-beta). Either 0.2 U bleomycin or saline was administered into left lung of TNF-alpha transgenic mice and their transgene-negative littermates. To overexpress TGF-beta, an adenovirus vector containing either active TGF-beta (AdTGF-beta) or LacZ was administered at a dose of 3 x 108 plaque-forming units per mouse. Fibrosis was assessed histologically and by measurement of hydroxyproline. TNF-alpha transgenic mice tolerated bleomycin or AdTGF-beta, whereas the transgene-negative littermates demonstrated severe pulmonary fibrosis after either agent. An increase in prostaglandin E2 and downregulation of TNF receptor I expression were observed in the TNF-alpha transgenic mice. In addition, recombinant human TNF-alpha attenuated bleomycin-induced pulmonary fibrosis. TNF-alpha has a complex role in the development of pulmonary fibrosis. Endogenous TNF-alpha may be important in the development of fibrosis as indicated in other reports, but overexpression of TNF-alpha or exogenous TNF-alpha limits pulmonary fibrosis in mice.

This study examined the optimum occlusal contacts of implant prostheses to maintain good oral condition after treatment. Three subjects who had two contiguously missing teeth (first and second molars) were selected. The displacement path of the implant, the adjacent tooth and the antagonistic tooth during clenching were measured using the type M-3 three-dimensional tooth displacement transducer. The occlusal contacts of implant prostheses changed according to the following four conditions. A contact: the inner inclination of the upper buccal cusp, B contact: the inner inclination of the upper lingual cusp, C contact: the outer inclination of the upper lingual cusp, and ABC contact: including the above three contacts. The measurements were performed at least six months after implant surgery. In each subject, the implants and the adjacent teeth were not affected by the change of the occlusal contact of the implant prosthesis, but the opposing teeth were affected. In the case of implantation in the lower side, the opposing tooth displaced in the buccal direction with A contact and C contact, which was a different direction to that of the natural tooth. The antagonist with B contact displaced in the lingual direction, which was the same direction as that of the natural tooth. The antagonist with ABC contact displaced in the lingual or buccal direction. It is concluded that the occlusal adjustment of implants needs much care: in the case of only A contact or C contact, non-physiological distortion might occur in periodontal tissues of the opposing teeth of the implant.

Implications: Acid aspiration syndrome remains a potentially critical perioperative complication. We compared lafutidine, ranitidine, and rabeprazole for reduction of preoperative gastric fluid acidity and volume in elective surgery and found that these variables were minimized with a single morning dose of lafutidine 20 mg compared with ranitidine or rabeprazole. Preoperative oral lafutidine may be an alternative to ranitidine as a prophylaxis against aspiration pneumonia.

The formation of benzocyclobutenol derivatives by intramolecular cyclizations of o-acylbenzyllithiums is described. Treatment of o-(trialkylsilylmethyl)phenyl ketones with lithium diisopropylamide (LDA) followed by quenching of the resulting benzylic carbanions with chlorotrialkylsilane resulted in stereoselective formation of the corresponding 1-trialkylsiloxy-2-(trialkylsilyl)benzocyclobutenes in good yields. Subsequently, o-acyl-m-methoxybenzyllithiums were found to work well in cyclization to benzocyclobuten-1-ol derivatives. The reaction of 2-benzoyl-3,4,5-trimethoxybenzyllithium, generated in situ by deprotonation of 6-methyl-2,3,4-trimethoxybenzophenone with LDA, with chlorotrimethylsilane afforded the corresponding 1-(trimethylsiloxy)benzocyclobutene. Cyclization of 2-pivaloyl-3-methoxybenzyllithiums, generated in situ from tert-butyl 2-methyl-6-methoxyphenyl ketones upon deprotonation with LDA, proceeded spontaneously even at -78 degrees C to give the corresponding benzocyclobuten-1-ols. We also describe the results of thermal isomerization of these 1-trimethylsiloxy-2-(trialkylsilyl)benzocyclobutenes.

Vinyl sulfoxides (PhSOCR(1)=CHR(2): R(1) = H, Me, or Ph; R(2) = H or Me) were treated with (dialkylamino)magnesium reagents, generated in situ from the reaction of EtMgBr with secondary amines (R(3)R(4)NH: R(3) = Et, i-Pr, or Bn; R(4) = Me, Et, or i-Pr) in refluxing Et(2)O for 1 h, and stirring at room-temperature overnight gave the corresponding symmetrical beta-(dialkylamino) dithioacetals [(PhS)(2)CR(1)CHR(2)NR(3)R(4)] in 24-84% yields. When the (diethylamino)magnesium reagent was treated with appropriate thiols (RSH; R = p-ClC(6)H(4) or Bn) prior to the interaction with phenyl vinyl sulfoxide, the corresponding unsymmetrical beta-(diethylamino) dithioacetals [(PhS)(RS)CHCH(2)NEt(2)] were produced in 63-67% yields.