bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tetra- and Di-Nuclear Copper(II) Complexes with Stereoisomers of Sulfinylcalix[4]arene Arising from the Disposition of Four S=O Groups
Authors: Iki Nobuhiko , Yamane Yusuke , Morohashi Naoya , Kajiwara Takashi , Ito Tasuku , Miyano Sotaro 
Published: June 2007

Abstract
A systematic investigation was conducted on the structures of tetra- and di-nuclear copper(II) complexes with three stereoisomers of sulfinylcalix[4]arenes (H4L), the isomerism of which is determined by the disposition of the sulfinyl oxygen with respect to a reference oxygen from the mean plane containing four sulfur atoms. The sulfinylcalix[4]arene with a trans–cis–trans S=O orientation (H4Lrtct) reacted with Cu(OAc)2 to form [CuII4(Lrtct)(OAc)3(μ-MeO)(MeOH)] (1), in which Lrtct4− adopts a cone conformation to afford tetrakis fac-tridentate coordination through four phenoxo oxygens and four sulfinyl groups giving a square CuII4 core. Ligands H4Lrccc and H4Lrctt having cis–cis–cis and cis–trans–trans configurations formed [CuII4(Lrccc)(OAc)3(μ-OH)] (2) and [CuII4(Lrctt)(OAc)3(μ-OH)] (3), respectively, which have common features, such as a cone-type conformation of L4−, tetrakis fac-tridentate coordination fashion, and tetracopper(II) core in a square-pyramidal geometry. The similarities among 1–3 clearly show that sulfinylcalix[4]arenes can coordinate to CuII in a fac-tridentate fashion via a donor atom X (O or S) from a sulfinyl group and two flanking phenoxo O−s and that X is simply determined by the X–Cu distance. Using [Cu(acac)2] as a copper(II) source, H4Lrctt formed [CuII2(H2Lrctt)2] (4), suggesting the significance of auxiliary ligand for bridging copper(II) centers to assemble the core, that is, the acetato ligands in complexes 1–3 are needed to form the core structure. Metal–metal interactions were investigated by means of magnetic susceptibility, and it was found that both ferro- and antiferromagnetic interactions occur in tetracopper(II) complex 3. In contrast, antiferromagnetic interaction is present in dicopper(II) complex 4.
Energy-Transfer Process in Crystals of Chiral and Racemic Double Complex Salts of [Co(ethylenediamine)3][Tb(2,6-pyridinedicarboxylate)3]
Authors: Iwamura Munetaka , Tsukuda Toshiaki , Morita Makoto 
Published: June 2007

Abstract
Luminescence and energy-transfer reactions in double complex crystals of [Co(en)3][Tb(dpa)3] (en = ethylenediamine, dpa = 2,6-pyridinedicarboxylate) were investigated and compared to single crystals of rac-[Co(en)3]·rac-[Tb(dpa)3] (double complexes salt of racemic [Co(en)3]3+ and racemic [Tb(dpa)3]3−) and Δ-[Co(en)3]·rac-[Tb(dpa)3] (chiral [Co(en)3]3+ and racemic [Tb(dpa)3]3− salt). The energy-transfer rate constants from Tb3+ to Co3+ complexes were determined from the time profile of emission intensity of photo-excited TbIII ion in the double complex crystals. The emission decay profiles of rac-[Co(en)3]·rac-[Tb(dpa)3] were analyzed with single exponential curves. On the other hand, the profiles of Δ-[Co(en)3]·rac-[Tb(dpa)3] show double-exponential curves. From the X-ray analysis of crystal structures, it was found that there is only one site for [Tb(dpa)3]3− in rac-[Co(en)3]·rac-[Tb(dpa)3] crystal, and there are two sites in the Δ-[Co(en)3]·rac-[Tb(dpa)3] crystal, i.e., Δ-[Tb(dpa)3]3− and Λ-[Tb(dpa)3]3− are put in different sites in the crystal. The two rate constants obtained from the double-exponential curve of Δ-[Co(en)3]·rac-[Tb(dpa)3] are assigned to energy-transfer rates from Δ-[Tb(dpa)3]3− and Λ-[Tb(dpa)3]3− in the crystal. A distance dependence was determined from the obtained energy-transfer rate constants and the Tb–Co distances in the crystals according to a Dexter type electron-exchange mechanism of energy-transfer model. The energy-transfer rate constants in the crystals are comparable in magnitude with energy-transfer rates in quenching experiments in the [Tb(dpa)3]3−–[Co(en)3]3+ aqueous solution.
Structural Details of a Fowl Feather Elucidated by Using Polarized Raman Microspectroscopy
Authors: Yokote Yoshiko , Kubo Yoshiko , Takahashi Rieko , Ikeda Teruki , Akahane Kiso , Tsuboi Masamichi 
Published: June 2007

Abstract
Raman spectra of undeuterated and deuterated rachis from a fowl feather was observed with 488 nm excitation in the 400–1800 cm−1 region. Fowl feather rachis and barbs were subjected to a polarized Raman microscopic examination with excitation at 785 nm. From the observed frequencies, intensities, and scattering anisotropies of the 20 Raman bands, and on the basis of known Raman tensors of the 10 localized molecular vibrations, conformations, and orientations of the polypeptide main chains, tyrosine, phenylalanine, tryptophan residues, and disulfide linkages of the protein molecules in the feather were elucidated.
Intramolecular Photocycloaddition of 2-(2-Alkenyloxymethyl)naphthalene-1-carbonitriles Using Glass-Made Microreactors
Authors: Mukae Hirofumi , Maeda Hajime , Nashihara Satoshi , Mizuno Kazuhiko 
Published: June 2007

Abstract
Intramolecular [2+2] and [2+3] photocycloadditions of 2-(2-alkenyloxymethyl)naphthalene-1-carbonitriles and their photocycloreversion using glass-made microreactors were investigated in comparison with photoreactions under conventional batch conditions. Both the efficiency and regioselectivity were improved by use of glass-made microreactors. These results can be explained by thorough absorption of light and outflow of primary product from the reaction system.
Synthesis and Relative Stereochemistry of the A- and F-Rings of Goniodomin A
Authors: Fujiwara Kenshu , Naka Jota , Katagiri Takahiro , Sato Daisuke , Kawai Hidetoshi , Suzuki Takanori 
Published: June 2007

Abstract
The synthesis of the A- and F-rings of goniodomin A (1), which is a stereochemically unidentified antifungal agent isolated from dinoflagellate Alexandrium hiranoi, was performed to determine of the relative stereochemistry of these parts. The relative stereochemistry of the A- and F-rings was first deduced from Murakami’s NMR data, and model compounds corresponding to these parts were then synthesized. The synthetic A-ring model, of which the structure was established by X-ray crystallographic analysis, showed good agreement with the natural A-ring on the basis of J and NOE behavior in the 1H NMR spectroscopy. The chemical shifts in 1H and 13C NMR specta and J32-OH–H33 of the synthetic F-ring model having a 33S,34R configuration also agreed with those of the F-ring of 1. Thus, the relative stereochemistry of the A- and F-rings of 1 was elucidated.
Approaches to the Potential Chirality of Bisguanidinobenzenes by Dynamic NMR Analysis
Authors: Nakanishi Waka , Ishikawa Tsutomu , Margetic Davor 
Published: June 2007

Abstract
The isomerization process, which is related to racemization of symmetrical 1,2-bis(diaminomethyleneamino)benzenes (=bisguanidinobenzenes) with potential chirality, is caused by bond rotation of aryl–(diaminomethyleneamino) (=aryl–guanidinyl) bond and/or diaminomethylene–imino (=guanidinyl imine) bond. This process was evaluated by temperature-dependent 1H NMR experiments. The guanidinyl imine bond rotation, which is important for the early stage of the inhibition of racemization process, was not restricted by substitution at the ortho-position of the benzene core or alkylation of guanidine function, while protonation of ortho-substituted bisguanidinobenzenes increased the rotation barrier. Changing the guanidine function from cyclic to acyclic caused the rotation about both bonds to become restricted, which could be observed by temperature-dependent 1H NMR experiments.
A New Type of Carbonylation of Styrenes Catalyzed by Pd(OAc)2 Combined with Molybdovanadophosphate
Authors: Yamada Shingo , Obora Yasushi , Sakaguchi Satoshi , Ishii Yasutaka 
Published: June 2007

Abstract
A new type of carbonylation of styrenes was achieved under a 1:1 mixture of CO (0.5 atm) and O2 (0.5 atm) in the presence of Pd(OAc)2 combined with H5PMo10V2O40·nH2O to give 4-methyl-2-phenylnaphthalen-1(4H)-one in 78% yield. Various substituted styrenes were also carbonylated to the corresponding substituted arylnaphthalen-1(4H)-ones in moderate yields. The reaction was found to proceed in two stages involving the head-to-tail dimerization of styrenes, followed by carbonylation of the resulting dimers. Styrenes were efficiently dimerized under air (1 atm) in the absence of CO even at room temperature to produce head-to-tail dimers in good yields.
An Entry to the Synthesis of Novel Nitrogen Macroheterocycles
Authors: Banerji Avijit , Bandyopadhyay Debasish , Basak Bidyut , Biswas Pizush Kanti , Banerji Julie , Chatterjee Asima 
Published: June 2007

Abstract
2,2′-Bi(1H-indolyl)-3,3′-dicarbaldehydes, prepared from 1H-indole-3-carbaldehydes by exploiting SET methodology, served as the key compound for synthesizing indolo[2,3-a]carbazoles as well as nitrogen macroheterocycles. Condensation of 2,2′-bi(1H-indolyl)-3,3′-dicarbaldehyde with aliphatic diamines produced Schiff’s base type compounds possessing a 10–14-membered ring.
Synthesis and Structure of a Kinetically Stabilized Stannanethione
Authors: Tajima Tomoyuki , Sasamori Takahiro , Takeda Nobuhiro , Tokitoh Norihiro 
Published: June 2007

Abstract
The X-ray crystallographic analysis of a stable stannanethione, Bbt(Titp)Sn=S, reveals that the tin–sulfur bond distance [2.221(3) Å] is ca. 10% shorter than the normal tin–sulfur single bonds and the tin atom of the stannanethione has a trigonal planar geometry, as do as the carbonyl carbon atoms.
Fragilide B: A Novel Briarane-Type Diterpenoid with a S-cis Diene Moiety
Authors: Sung Ping-Jyun , Chen Yu-Pei , Su Yu-Mine , Hwang Tsong-Long , Hu Wan-Ping , Fan Tung-Yung , Wang Wei-Hsien 
Published: June 2007

Abstract
A novel chlorinated briarane derivative, fragilide B (1), was isolated from the Formosan gorgonian coral Junceella fragilis. Fragilide B (1) possesses a s-cis diene moiety in the structure. The structure of 1 was elucidated by interpretation of spectral data and further supported by molecular mechanics calculations.
Rapid Fabrication of a Smooth Hollow-Spheres Array
Authors: Matsushita Sachiko , Fujikawa Shigenori , Onoue Shinya , Kunitake Toyoki , Shimomura Masatsugu 
Published: June 2007

Abstract
A smooth TiO2 hollow-spheres array, a kind of inverse opals, was prepared in a wide area (&gt; 1 × 5 cm) in a short time (less than 1 min excluding sintering) using a spin-coating technique. A two-dimensional colloidal crystal was used as a template. The TiO2 sintering process, especially the rate of the temperature increase, was important to copy the periodicity of the colloidal crystal structure. The electron diffraction image taken by the transmission electron microscopy observation showed that the hollow-spheres arrays have anatase-type crystal structure.
Myopathy and steatitis in the common guppy, Poecilia (Lebistes)reticulata (Peters)
Authors: Helder Th. 
Published: June 2007

Summary There was 1% mortality among female guppies just imported from Southeast Asia. Moribund fish showed discoloration, lethargy and kyphosis. Microscopically, myopathy and steatitis were observed, together with an extensive ceroid storage. These findings are indicative of vitamin E deficiency, and illustraee the risk of using fish of unknown origin in toxicological studies.
Genic heterogeneity and genetic monitoring of mouse outbred stocks
Authors: Groen A. , Lagerwerf A. J. 
Published: June 2007

Summary An outbred stock of Swiss :SE mice has been surveyed for genic heterogeneity at 12 loci, encoding biochemical polymorphisms in mice. Using horizontal starch-gel electrophoresis, 6 loci (Es-1, Es-2, Es-3, Es-5, Trf, Dip-1) revealed no genic heterogeneity within the total sample of 289 male mice examined. The other 6 loci (Mpi-1, Mup-1, Hbb, Gpi-1, Pgm-1, Ldr-1) each showed a 2–allelic variation within each of the 3 stock units (pavilions) involved. A pavilion effect on the observed genotype numbers was found for Pgm-1 and Gpi-1 (P < 0·10). Inadequate genotyping may have occurred at Gpi-1 and Ldr-1, as suggested by a 'week effect' on the observed genotype numbers (P < 0·05). For studying long-term genetic changes within outbred stocks, a routine monitoring procedure using biochemical polymorphisms is recommended.
Ultrastructure of rhesus monkey renomedullary interstitial cells
Authors: Lewis David J. , Prentice David E. 
Published: June 2007

Summary The fine structure of rhesus monkey renomedullary interstitial cells was studied by electron microscopy. These stellate cells contained variable numbers of lipid droplets, moderate numbers of mitochondria, moderate amounts of rough endoplasmic reticulum, and prominent Golgi zones. In rare instances, apparent release of lipid droplets into the interstitium was observed. The most prominent feature of the interstitial cells was large nuclear pseudoinclusions which were observed in a high proportion of the animals examined.
Differentiation of various experimentally-induced pathological processes in Wistar rats by serum protein electrophoresis using cellulose-acetate membranes
Authors: Rothkopf-Ischebeck Margret 
Published: June 2007

Plasma protein profiles were investigated electrophoretically in rats with aminonucleoside-induced glomerular damage, uranyl-nitrate-induced tubular damage, phalloidin-induced hepatocyte membrane damage, adjuvant arthritis as a model of chronic inflammation, and phenyl isothiocyanate pleurisy as a model of acute inflammation. Characteristic profiles were observed for each experimental disease, and their development and seriousness could be evaluated. Similar studies are already routinely used in clinical investigations of human plasma.
Probable Warfarin–Simvastatin Interaction
Authors: Westergren Tone , Johansson Peder , Molden Espen 
Published: June 2007

Objective: To report and discuss a case of fatal cerebral hemorrhage following a switch from atorvastatin to simvastatin in a patient taking warfarin. Case Summary: An 82-year-old white female was admitted to the hospital because of an international normalized ratio (INR) value greater than 8, which was detected at a routine follow-up visit to monitor warfarin therapy. Four weeks earlier her lipid-lowering therapy had been switched from atorvastatin 10 mg daily to simvastatin 10 mg daily. She had been treated with 2.5 mg of warfarin daily for almost 30 years due to episodes of deep venous thrombosis and lung embolism. Her INR had been stable within the treatment range (2.0–3.5) for more than 2 years before the INR increase. Upon hospitalization, she was given 5 mg of vitamin K orally, A few hours later she lost the feeling and movement of her right arm and a computed tomography scan showed major bleeding in the left cerebral hemisphere. She died the following day. Discussion: One study has shown a lack of interaction between warfarin and atorvastatin. In comparison, 3 studies have shown significant increases (10–30%) in warfarin effect and/or reductions in dose requirement after starling concomitant simvastatin treatment. The interaction mechanism between simvastatin and warfarin is not known but is possibly associated with reduced elimination of warfarin. Use of the Naranjo probability scale showed that the likelihood of warfarin-induced INR increase following the switch to simvastatin was probable. Conclusions: Atorvastatin and simvastatin appear to differ in their potential to interact with warfarin. Clinicians should be aware of the interaction risk when starting simvastatin treatment in patients on warfarin therapy.
Estimating Differential Reproductive Success From Nests of Related Individuals, With Application to a Study of the Mottled Sculpin,Cottus bairdi
Authors: Jones Beatrix , Grossman Gary D , Walsh Daniel C I , Porter Brady A , Avise John C , Fiumera Anthony C 
Published: June 2007

AbstractUnderstanding how variation in reproductive success is related to demography is a critical component in understanding the life history of an organism. Parentage analysis using molecular markers can be used to estimate the reproductive success of different groups of individuals in natural populations. Previous models have been developed for cases where offspring are random samples from the population but these models do not account for the presence of full- and half-sibs commonly found in large clutches of many organisms. Here we develop a model for comparing reproductive success among different groups of individuals that explicitly incorporates within-nest relatedness. Inference for the parameters of the model is done in a Bayesian framework, where we sample from the joint posterior of parental assignments and fertility parameters. We use computer simulations to determine how well our model recovers known parameters and investigate how various data collection scenarios (varying the number of nests or the number of offspring) affect the estimates. We then apply our model to compare reproductive success among different age groups of mottled sculpin, Cottus bairdi, from a natural population. We demonstrate that older adults are more likely to contribute to a nest and that females in the older age groups contribute more eggs to a nest than younger individuals.
Estimation of Multilocus Linkage Disequilibria in Diploid Populations With Dominant Markers
Authors: Li Yanchun , Li Yang , Wu Song , Han Kun , Wang Zhengjia , Hou Wei , Zeng Yanru , Wu Rongling 
Published: June 2007

Abstract
Analysis of population structure and organization with DNA-based markers can provide important information regarding the history and evolution of a species. Linkage disequilibrium (LD) analysis based on allelic associations between different loci is emerging as a viable tool to unravel the genetic basis of population differentiation. In this article, we derive the EM algorithm to obtain the maximum-likelihood estimates of the linkage disequilibria between dominant markers, to study the patterns of genetic diversity for a diploid species. The algorithm was expanded to estimate and test linkage disequilibria of different orders among three dominant markers and can be technically extended to manipulate an arbitrary number of dominant markers. The feasibility of the proposed algorithm is validated by an example of population genetic studies of hickory trees, native to southeastern China, using dominant random amplified polymorphic DNA markers. Extensive simulation studies were performed to investigate the statistical properties of this algorithm. The precision of the estimates of linkage disequilibrium between dominant markers was compared with that between codominant markers. Results from simulation studies suggest that three-locus LD analysis displays increased power of LD detection relative to two-locus LD analysis. This algorithm is useful for studying the pattern and amount of genetic variation within and among populations.
The Molecular Chaperone Hsp90 Is Required for mRNA Localization in Drosophila melanogaster Embryos
Authors: Song Yan , Fee Lanette , Lee Tammy H , Wharton Robin P 
Published: June 2007

Abstract
Localization of maternal nanos mRNA to the posterior pole is essential for development of both the abdominal segments and primordial germ cells in the Drosophila embryo. Unlike maternal mRNAs such as bicoid and oskar that are localized by directed transport along microtubules, nanos is thought to be trapped as it swirls past the posterior pole during cytoplasmic streaming. Anchoring of nanos depends on integrity of the actin cytoskeleton and the pole plasm; other factors involved specifically in its localization have not been described to date. Here we use genetic approaches to show that the Hsp90 chaperone (encoded by Hsp83 in Drosophila) is a localization factor for two mRNAs, nanos and pgc. Other components of the pole plasm are localized normally when Hsp90 function is partially compromised, suggesting a specific role for the chaperone in localization of nanos and pgc mRNAs. Although the mechanism by which Hsp90 acts is unclear, we find that levels of the LKB1 kinase are reduced in Hsp83 mutant egg chambers and that localization of pgc (but not nos) is rescued upon overexpression of LKB1 in such mutants. These observations suggest that LKB1 is a primary Hsp90 target for pgc localization and that other Hsp90 partners mediate localization of nos.
Efficient Tor Signaling Requires a Functional Class C Vps Protein Complex in Saccharomyces cerevisiae
Authors: Zurita-Martinez Sara A , Puria Rekha , Pan Xuewen , Boeke Jef D , Cardenas Maria E 
Published: June 2007

Abstract
The Tor kinases regulate responses to nutrients and control cell growth. Unlike most organisms that only contain one Tor protein, Saccharomyces cerevisiae expresses two, Tor1 and Tor2, which are thought to share all of the rapamycin-sensitive functions attributable to Tor signaling. Here we conducted a genetic screen that defined the global TOR1 synthetic fitness or lethal interaction gene network. This screen identified mutations in distinctive functional categories that impaired vacuolar function, including components of the EGO/Gse and PAS complexes that reduce fitness. In addition, tor1 is lethal in combination with mutations in class C Vps complex components. We find that Tor1 does not regulate the known function of the class C Vps complex in protein sorting. Instead class C vps mutants fail to recover from rapamycin-induced growth arrest or to survive nitrogen starvation and have low levels of amino acids. Remarkably, addition of glutamate or glutamine restores viability to a tor1 pep3 mutant strain. We conclude that Tor1 is more effective than Tor2 at providing rapamycin-sensitive Tor signaling under conditions of amino acid limitation, and that an intact class C Vps complex is required to mediate intracellular amino acid homeostasis for efficient Tor signaling.
Using Reporter Gene Assays to IdentifycisRegulatory Differences Between Humans and Chimpanzees
Authors: Chabot Adrien , Shrit Ralla A , Blekhman Ran , Gilad Yoav 
Published: June 2007

AbstractMost phenotypic differences between human and chimpanzee are likely to result from differences in gene regulation, rather than changes to protein-coding regions. To date, however, only a handful of human–chimpanzee nucleotide differences leading to changes in gene regulation have been identified. To hone in on differences in regulatory elements between human and chimpanzee, we focused on 10 genes that were previously found to be differentially expressed between the two species. We then designed reporter gene assays for the putative human and chimpanzee promoters of the 10 genes. Of seven promoters that we found to be active in human liver cell lines, human and chimpanzee promoters had significantly different activity in four cases, three of which recapitulated the gene expression difference seen in the microarray experiment. For these three genes, we were therefore able to demonstrate that a change in cis influences expression differences between humans and chimpanzees. Moreover, using site-directed mutagenesis on one construct, the promoter for the DDA3 gene, we were able to identify three nucleotides that together lead to a cis regulatory difference between the species. High-throughput application of this approach can provide a map of regulatory element differences between humans and our close evolutionary relatives.