bluuebunny/crossref_metadata_2025_split huggingface dataset:
π-Radical Cationic Salts of Tetrathiafulvalene Derivatives with Pyromellitate
Authors: Shiono Kazuhiko , Naito Toshio , Inabe Tamotsu 
Published: March 2007

Abstract
Pyromellitate is known to form hydrogen-bonding anionic networks when the number of deprotonation from pyromellitic acid is one or two. This unique anion has been utilized for the construction of the π-radical cationic salts of the tetrathiafulvalene (TTF) derivatives. In the crystals of three kinds of the TTF salts and the tetramethyltetraselenafulvalene salt, pyromellitate was found to form two-dimensional sheets. The anions in the two TTF salts were connected by rhombic-type inter-anionic connection, which is a typical inter-anionic connection pattern for pyromellitate. The TTF derivatives were all in a π-radical mono-cationic state and dimerized in a space dictated by the anionic networks. The extra space in the crystals was filled with crystal solvents. On the other hand, in the crystals of the ethylenedithia-tetrathiafulvalene salts, pyromellitate formed only intra-molecular hydrogen bonds. The anion was thus isolated in these crystals.
Spin-Trapping Properties of 5-(Diphenylphosphinoyl)-5-methyl-4,5-dihydro-3H-pyrrole N-Oxide (DPPMDPO)
Authors: Nishizawa Masahiro , Shioji Kosei , Kurauchi Yoshimitsu , Okuma Kentaro , Kohno Masahiro 
Published: March 2007

Abstract
Spin-trapping properties of a novel spin-trapping reagent, 5-(diphenylphosphinoyl)-5-methyl-4,5-dihydro-3H-pyrrole N-oxide (DPPMDPO), were investigated by ESR spectroscopy. DPPMDPO had larger rate constants than DMPO and DEPMPO. DPPMDPO should be better than DEPMPO as a spin-trapping reagent for superoxide detection.
Synthesis and Spectroscopic Characterization of New Molecular Complexes of Bismuth(III) Chloride with Free Base meso-Tetraarylporphyrins
Authors: Dehghani Hossein , Ansari Sardrood Ali Reza 
Published: March 2007

Abstract
Reaction of bismuth(III) chloride (BiCl3) with free base meso-tetraarylporphyrins (H2t(X)pp, X = 4-Me, 4-OMe, 3-Me, 3-OMe, and H) in CHCl3 under mild conditions gives exclusively 1:1 molecular complexes with the general formula [(BiCl3{H2t(X)pp})2]. The remarkable agreement between 1H and 13C NMR and UV–vis spectra of the porphyrin macrocycle in these complexes and those of meso-tetraarylporphyrin molecular complexes with DDQ, TCNE, SiR3Cl, and BF3 indicates that they all have a similar porphyrin core. The molecular complexes have a dimer structure containing a Bi2Cl6 moiety. In the proposed structures for the complexes, four pyrroles are tilted alternatively up and down with respect the porphyrin mean plane, which leads to the appropriate orientation of the nitrogen lone pairs towards the central bismuth atoms. Therefore, octahedral geometry for the bismuth center is proposed.
Chemical Conversion of Natural Polymyxin B and Colistin to Their N-Terminal Derivatives
Authors: Okimura Keiko , Ohki Kazuhiro , Sato Yuki , Ohnishi Kuniharu , Uchida Yoshiki , Sakura Naoki 
Published: March 2007

Abstract
The chemical conversions of natural polymyxin B and colistin, which are fatty-acylated cyclic decapeptides, to polymyxin (2–10) and colistin (2–10) derivatives were examined. The Nα-free and side chain Nγ-protected nonapeptides, i.e., tetrakis(Nγ-trifluoroacetyl)–polymyxin B (2–10) and tetrakis(Nγ-trifluoroacetyl)–colistin (2–10), were prepared by trifluoroacetylation of polymyxin B and colistin, followed by chemical cleavage with 50% methanesulfonic acid to remove Nα-alkanoyl–Nγ-trifluoroacetyl–Dab–OH. The Nγ-protected nonapeptides were useful starting materials for the semi-synthesis of N-terminal derivatives by selective Nα-acylation at Thr2, followed by the removal of the Nγ-trifluoroacetyl protecting group with aqueous piperidine. Further, myristoyl–polymyxin B (2–10) and myristoyl–colistin (2–10) retained their antimicrobial activity with an MIC of 2–4 nmol mL−1 against Escherichia coli, Salmonella Typhimurium, and Pseudomonas aeruginosa. They also retained their high lipopolysaccahride (LPS) binding activity. Acetyl–polymyxin B (2–10) and acetyl–colistin (2–10) exhibited very low biological activities, except for a high bactericidal activity specifically against Pseudomonas aeruginosa with an MIC of 2 nmol mL−1. The distinct sensitivity of three Gram-negative bacteria tested toward acetyl-nonapeptides suggested that the N-terminal hydrophobic character of the fatty-acylated polymyxin peptides was necessary for the bactericidal activity against Escherichia coli and Salmonella Typhimurium, but not against Pseudomonas aeruginosa.
Ionic Liquid [bmim]PF6-Mediated Synthesis of 1,2-Orthoesters of Carbohydrates and the Glycosidation Reactions of 4-Pentenyl Orthoesters
Authors: Anas Saithalavi , Sajisha Valiyaveetil Sanjayan , Rajan Rani , Kumaran Rajasekaran Thirumalai , Radhakrishnan Kokkuvayil Vasu 
Published: March 2007

Abstract
A facile synthesis of the 1,2-orthoesters of carbohydrates in the ionic liquid [bmim]PF6 without a quaternary ammonium salt like tetrabutylammonium iodide, is described. The glycosidation reactions of 4-pentenyl orthoesters (NPOEs) with different alcohols are also discussed. The work described in this paper showed that [bmim]PF6 is an efficient and recyclable solvent for the synthesis and glycosidation reaction of orthoesters.
The Effect of meta-Substitution on the Photochemical Properties of Benzoxazole Derivatives
Authors: Ohshima Asuka , Ikegami Masashi , Shinohara Yoshihiro , Momotake Atsuya , Arai Tatsuo 
Published: March 2007

Abstract
The photochemistry of 2-(2-hydroxy-3-methoxyphenyl)benzoxazole (3-MHBO) and 2-(2-hydroxy-4-methoxyphenyl)benzoxazole (4-MHBO) have been investigated. The excited-state properties of 4-MHBO were similar to those for the parent compound 2-(2-hydroxyphenyl)benzoxazole (HBO), whereas different properties were observed for 3-MHBO. 4-MHBO in benzene exhibited large Stokes-shifted fluorescence from the keto-form in the excited singlet state (KE*) after excited-state intramolecular proton transfer (ESIPT), whereas 3-MHBO emitted dual fluorescence from E* and KE* species. Fluorescence due to KE* for 3-MHBO (λmax = 525 nm) occurred at a considerably longer wavelength than that of 4-MHBO (λmax = 480 nm). The fluorescence efficiency of 3-MHBO (Φf = 0.002) was much smaller than those of 4-MHBO and HBO (Φf = 0.018 and 0.02, respectively). These results are consistent with suppression of ESIPT, stabilization of KE* species, and acceleration of non-radiative decay, probably because of the formation of a hydrogen bond between phenol oxygen and methoxy hydrogen at 3-position in 3-MHBO. Thus, 3-MHBO displayed a meta-substituent effect involving the relaxation pathway of excited state HBO derivatives.
Synthesis of Isochalcogenazole Rings by Treating β-(N,N-Dimethylcarbamoylchalcogenenyl)alkenyl Ketones with Hydroxylamine-O-sulfonic Acid
Authors: Shimada Kazuaki , Moro-oka Akiko , Maruyama Akiko , Fujisawa Hiroyuki , Saito Toshio , Kawamura Ryo , Kogawa Hisashi , Sakuraba Maiko , Takata Yukichi , Aoyagi Shigenobu , Takikawa Yuji , Kabuto Chizuko 
Published: March 2007

Abstract
β-(N,N-Dimethylcarbamoylselenenyl)- and β-(N,N-dimethylcarbamoyltellurenyl)alkenyl ketones were converted into isoselenazoles and isotellurazole Te-oxides, respectively, simply by treating with hydroxylamine-O-sulfonic acid, and deoxygenation of the latter products was successfully carried out by treating with PPh3. Alternative treatment of ynone oxime tosylates with hydrochalcogenide ions or N,N-dimethylchalcogenocarbamate ions also gave the same isochalcogenazole rings. These reactions were assumed to proceed through intramolecular nucleophilic substitution on the nitrogen atom of oxime sulfonates by the attack of in situ generated chalcogen nucleophiles.
Efficient Synthesis of Propargylic Ethers under the DBU Conditions and Its Application to Natural Products Synthesis
Authors: Yokoyama Tadashi , Kutsumura Noriki , Ohgiya Tadaaki , Nishiyama Shigeru 
Published: March 2007

Abstract
Conversion of dibromides carrying O-functional groups at adjacent positions to the corresponding propargylic ethers was successfully carried out under the DBU conditions through 2-bromo-1-alkenes as intermediates. The optically active γ-lactone-class natural products, such as (−)-muricatacin (4) and (R,R)-sapinofuranone B (5) were synthesized using the propargylic ether intermediate produced by the elimination reaction mentioned above.
Detoxification of Antimonic Contaminated Water and Precipitation Recovery of Antimony by Mineralization under Hydrothermal Condition
Authors: Itakura Takeshi , Sasai Ryo , Itoh Hideaki 
Published: March 2007

Abstract
The detoxification of water contaminated by antimony and its resource recovery are achieved by hydrothermal mineralization treatment. The treatment is based on the precipitation method of a mineral from aqueous media by imitating natural mineralization mechanism derived from activity of magma. The treatment could reduce Sb concentration in aqueous media, when the formed mineral was Ca2(Sb2O7), which resembled natural mineral of Monimolite ((Pb,Ca)2Sb2O7). The antimony concentration in water after the hydrothermal mineralization under optimal conditions was 0.06 mg/dm3. Additionally, the rapid cooling of the treated water made much progress in the treatment efficiency to disturb the re-dissolution of the formed mineral. Therefore, this treatment is effective for detoxification of water polluted by antimonic species and its resource recovery.
Decomposition of Toluene by Atmospheric Pressure Microwave Plasma Generated Using Metal Salt-impregnated Carbon Felt Pieces
Authors: Kurihara Hideki , Yajima Tatuhiko 
Published: March 2007

Abstract
Atmospheric pressure microwave plasma (APMP) could be easily generated even in air by using carbon felt pieces impregnated with a metal salt such as alkali metal chlorides, alkali earth metal chlorides, and so on (CF/metal salt). As one of applications, the decomposition and complete removal of toluene, one of volatile organic compounds (VOCs) as environmental air pollutants, with APMP assisted by CF/NaCl and CF/CaCl2 was examined. Consequently, we succeeded in decomposing and removing it completely without carbon monoxide formation and CF consumption.
Antireflection Polymer Surface Using Anodic Porous Alumina Molds with Tapered Holes
Authors: Yanagishita Takashi , Yasui Kenji , Kondo Toshiaki , Kawamoto Yasushi , Nishio Kazuyuki , Masuda Hideki 
Published: March 2007

Abstract
Antireflection (AR) polymer structures composed of tapered conical pillars were fabricated using highly ordered anodic porous alumina. The shape of the holes in the anodic porous alumina was controlled by performing repeated anodization and pore-widening treatments. By replicating the structure of the anodic porous alumina with PMMA, polymer AR structures were obtained.
One-pot Synthesis of α-Alkoxy Azides from Carbonyl Compounds Catalyzed by Iron(III) Chloride
Authors: Omura Megumi , Iwanami Katsuyuki , Oriyama Takeshi 
Published: March 2007

Abstract
In the presence of alkoxytrimethylsilane and a catalytic amount of iron(III) chloride, the reaction of various carbonyl compounds with trimethylsilyl azide afforded the corresponding α-alkoxy azides. This reaction could be suitable especially for azidation of aromatic aldehydes and proceeds under mild conditions in a convenient one-pot manner.
Preparation of Three-dimensionally Ordered Macroporous Oxides by Combining Templating Method with Sol–Gel Technique
Authors: Li Shi , Zheng Jingtang , Yang Weiya , Zhao Yucui 
Published: March 2007

Abstract
Three-dimensionally ordered macroporous (3DOM) inorganic oxides, SiO2 and TiO2, have been synthesized by combining template-assisted colloidal method with sol–gel technique. Close-packed PS beads were first prepared as template by using gravitational sedimentation, followed by infiltration with corresponding sol precursors rather than corresponding alkoxides, and then templates were removed by calcination. The morphology and crystalloid structure of samples were investigated by SEM and XRD, respectively. The results indicate that the structures of samples are well-inverse replicas of PS template and the method is also applicable to the preparation of other oxides.
Synthesis and Characterization of Hydride and Carbonyl RuMo3S4 Cubane Clusters
Authors: Takei Izuru , Kobayashi Koji , Dohki Keita , Nagao Shoken , Mizobe Yasushi , Hidai Masanobu 
Published: March 2007

Abstract
Treatment of [(Cp*Mo)3(μ3-S)4RuH2(PPh3)][PF6] (1; Cp* = η5-C5Me5) with aqueous HCl afforded the trichloride cluster [(Cp*Mo)3(μ3-S)4RuCl3] (2), which was reduced with Cp2Co in the presence of PR3 under H2 to give the hydride cluster [(Cp*Mo)3(μ3-S)4RuH(PR3)] (R = Cy (3a), i-Pr (3b); Cy = cyclo-C6H11). Cluster 3 was further converted into the chloride cluster [(Cp*Mo)3(μ3-S)4RuCl(PR3)] (R = Cy (4a), i-Pr (4b)) by reaction with CCl4. Reaction of cluster 4 with NaPF6 under CO resulted in the formation of the carbonyl cluster [(Cp*Mo)3(μ3-S)4Ru(CO)(PR3)][PF6] (R = Cy (5a), i-Pr (5b)), while the reaction under H2 gave the dihydride cluster [(Cp*Mo)3(μ3-S)4RuH2(PR3)][PF6] (R = Cy (6a), i-Pr (6b)).
Vitamin D Receptor 3′ Haplotypes Are Unequally Expressed in Primary Human Bone Cells and Associated With Increased Fracture Risk: The MrOS Study in Sweden and Hong Kong
Authors: Grundberg Elin , Lau Edith MC , Pastinen Tomi , Kindmark Andreas , Nilsson Olof , Ljunggren Östen , Mellström Dan , Orwoll Eric , Redlund-Johnell Inga , Holmberg Anna , Gurd Scott , Leung Ping Chung , Kwok Timothy , Ohlsson Claes , Mallmin Hans , Brändström Helena 
Published: March 2007

Abstract
The VDR is a prime candidate gene for osteoporosis. Here, we studied three common VDR haplotypes in relation to bone phenotypes in 5014 participants of the global MrOS Study. We also studied the relative expression of the haplotypes in human bone cells. One haplotype was associated with increased fracture risk and differently expressed in primary human bone cells.
Introduction: Vitamin D plays an essential role in skeletal metabolism by binding to its nuclear steroid receptor, the vitamin D receptor (VDR). The heritability of BMD is well established, and the VDR gene is considered a prime candidate suggested to partially account for genetically controlled BMD variance in the population.
Materials and Methods: Here, we reconstructed common haplotypes in the VDR 3′ untranslated region (UTR) and studied the association to BMD and risk of vertebral fractures in elderly men from Sweden (n = 3014) and Hong Kong (n = 2000), all participants of the global MrOS Study. To assess any functional implications of the VDR polymorphisms, we studied allele-specific expressions of the different VDR 3′ UTR haplotypes in the normal chromosomal context of 70 unrelated human trabecular bone samples. This was performed by quantitative genotyping of coding polymorphisms in RNA samples and in corresponding DNA samples isolated from the bone samples.
Results: Three major haplotypes were reconstructed and in agreement with the previously well-defined baT, BAt, and bAT haplotypes, herein denoted Hap1, Hap2, and Hap3. The Hap1 haplotype was independently associated with increased risk of vertebral fractures in Swedish men (OR, 1.655; 95% CI, 1.146–2.391; p &lt; 0.01) and with lower lumbar spine BMD in elderly men from Sweden (p &lt; 0.01) and Hong Kong (p &lt; 0.05). The VDR gene was also shown to exhibit a 3′ UTR haplotype dependent allelic imbalance, indicating that the VDR Hap1 allele was overexpressed in human trabecular bone samples.
Conclusions: The results indicate that the relatively overexpressed VDR Hap1 haplotype could be considered a risk allele for osteoporosis regardless of ethnicity.
Exclusion of Focal Vertebral Artifacts From Spine Bone Densitometry and Fracture Prediction: A Comparison of Expert Physicians, Three Computer Algorithms, and the Minimum Vertebra
Authors: Tsang James F , Leslie William D 
Published: March 2007

Abstract
Expert physicians and automated methods for the exclusion of vertebral levels in DXA scans containing focal artifacts were compared. All methods of vertebral exclusion led to a small improvement in fracture prediction. Computer algorithms performed at least as well as physicians.
Introduction: Lumbar spine DXA is often confounded by focal artifacts. Clinical rules and automated methods for vertebral exclusion have been proposed, but their concordance, effect on diagnosis, and fracture prediction is unknown.
Materials and Methods: We analyzed clinical DXA scans of the lumbar spine (20,478 women and 1534 men) performed from 1998 to 2002 (Province of Manitoba, Canada). Longitudinal health service records were assessed for the presence of nontrauma fracture codes after BMD testing. The effect of vertebral exclusions by expert physicians and several automated methods on diagnosis and prediction of incident fractures was compared.
Results: Vertebral exclusions were reported by physicians in over one quarter of the scans (31% of women and 29% of men). All methods of vertebral exclusion significantly decreased the mean spine T-score and increased the proportion of women designated as osteoporotic. κ values and ROC area under the curve (AUC) for physician-computer agreement in the identification of abnormal scans indicated fair to moderate agreement in both women and men. Compared with no vertebral exclusions, a small increase in the hazard ratio and AUC for spine fracture and osteoporotic fracture prediction was seen after physician and computer exclusions. Compared with physician exclusions, AUC for prediction of osteoporotic fractures in men increased significantly with one computer algorithm (p = 0.004). The minimum vertebral T-score enhanced fracture prediction compared with no exclusions but approximately doubled the prevalence of osteoporotic categorization.
Conclusions: We observed fair to moderate agreement between the physician and computer methods for vertebral level exclusion. All methods of vertebral exclusion led to a small improvement in fracture prediction using the lumbar spine measurement. The automated algorithms performed at least as well as physicians when fractures were used as the endpoint.
Ten-Year Risk of Osteoporotic Fractures in Postmenopausal Chinese Women According to Clinical Risk Factors and BMD T-Scores: A Prospective Study
Authors: Kung Annie W C , Lee Ka-Kui , Ho Andrew Y Y , Tang Grace , Luk Keith D K 
Published: March 2007

Abstract
Independent risk factors for osteoporotic fracture were identified for a Southern Chinese postmenopausal population. Clinical risk factor assessment with or without BMD measurement was shown to be an effective predictor of 10-yr risk of osteoporotic fracture and provides a more accessible tool for patient evaluation.
Introduction: Asian-specific data on risk factors for osteoporosis remain sparse. However, risk factor assessment, in addition to BMD measurement, is increasingly recognized as a reliable predictor of absolute osteoporotic fracture risk. The purpose of this prospective study was to determine the specific independent risk factors for osteoporotic fracture and to predict the 10-yr risk of osteoporotic fracture in the postmenopausal Southern Chinese population.
Materials and Methods: A total of 1435 community-dwelling, postmenopausal, treatment-naive women were recruited. Baseline demographic characteristics and clinical risk factors were obtained, and BMD at the spine and hip was measured. Subjects were followed for outcomes of incident low trauma fracture. Ten-year risk of osteoporotic fracture was predicted from the risk factor assessment and BMD measurement by Cox proportional hazards models.
Results: The mean age of subjects was 63.4 ± 8.3 yr. After 5.0 ± 2.3 yr (range, 1.0–11.0 yr) of follow-up, 80 nontraumatic new fractures were reported during follow-up. Eight independent clinical risk factors identified at baseline were found to be significant predictors of osteoporotic fracture, with the most important being use of walking aids (RR, 4.2; 95% CI, 2.7–6.7; p &lt; 0.001) and a history of fall (RR, 4.0; 95% CI, 2.5–6.2; p &lt; 0.001). Other predictive factors included being homebound, calcium intake &lt; 400 mg/d, age &gt; 65 yr, history of fracture, and BMI &lt; 19 kg/cm2. Subjects with three to eight clinical risk factors had a predicted 10-year risk of osteoporotic fracture of 25%, which increased to 30% if they also had total hip BMD T-score ≤ −2.5.
Conclusions: Clinical risk factor assessment, with or without BMD measurement, is a reliable predictor of 10-year risk of osteoporotic fracture and may be particularly useful in regions or primary care clinics without access to bone densitometry equipment.
Implementation of a Combined Association-Linkage Model for Quantitative Traits in Linear Mixed Model Procedures of Statistical Packages
Authors: Beem A. Leo , Boomsma Dorret I. 
Published: March 2007

AbstractA transmission disequilibrium test for quantitative traits which combines association and linkage analyses is currently available in several dedicated software packages. We describe how to implement such models in linear mixed model procedures that are available in widely used statistical packages such as SPSS. We also briefly mention a few extensions of the model that become naturally available once the model is implemented in such procedures.
Effects of Angiotensinogen and Angiotensin II Type I Receptor Genes on Blood Pressure and Left Ventricular Mass Trajectories in Multiethnic Youth
Authors: Wang Xiaoling , Zhu Haidong , Dong Yanbin , Treiber Frank A. , Snieder Harold 
Published: March 2007

AbstractThe objective of this study was to evaluate the impact of variations of the angiotensinogen (AGT) and angiotensin II type I receptor (AGTR1) genes on progression of blood pressure (BP) and left ventricular mass (LVM) in multiethnic youth. The study was longitudinal involving 581 European American (EA) and African American (AA) youth with 12 assessments over a 15-year period. AGT M235T and three AGTR1 polymorphisms (C-521T, L191L and A1166C) were genotyped and individual growth curve modeling analyses were conducted. Single nucleotide polymorphism (SNP) analyses found a significant 3-way interaction between M235T, ethnicity and gender on BP levels. Systolic BP (SBP) levels were 5.8 mmHg (p = .00003) and diastolic BP (DBP) levels were 2.6 mmHg (p = .005) lower in carriers versus noncarriers of the M235 allele in AA males only. Furthermore, the AGTR1 L191 allele showed a SBP lowering effect in subjects with a high socioeconomic status (SES; p = .048) and a DBP lowering effect in AAs (p = .038). Haplotype analyses identified a protective haplotype (C-521, 191L and A1166) for LVM levels (p = .03). LVM in individuals homozygous for this haplotype was 12.9 g lower than those homozygous for the most common haplotype (–521T, 191L and A1166). No significant interactions were found between the AGT M235T polymorphism and any of the single SNPs or haplotypes of the AGTR1 gene. Our results in multiethnic youth uncover an ethnicity and gender-specific effect of the AGT M235T polymorphism and a SES or ethnicity-specific effect of the AGTR1 L191L polymorphism on the progression of hypertension risk. A protective AGTR1 haplotype for LVM was also identified.