bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and Biological Evaluation of the Trifluoromethyl Analog of (4S)‐4,5‐Dihydroxy‐2,3‐pentanedione (DPD)
Authors: Frezza Marine , Balestrino Damien , Soulère Laurent , Reverchon Sylvie , Queneau Yves , Forestier Christiane , Doutheau Alain 
Published: August 2006

AbstractThe asymmetric synthesis of the trifluoromethyl analogue of (4S)‐4,5‐dihydroxy‐2,3‐pentanedione [(4S)‐DPD], the metabolic precursor of the bacterial quorum sensing (QS) autoinducer AI‐2, is described. The trifluoromethyl group was introduced by treating (trifluoromethyl)trimethylsilane with an α‐methylene ester resulting from a Baylis–Hillman reaction between (tert‐butyldimethylsilyloxy)acetaldehyde and a vinylamide derived from Oppolzer’s sultam reagent. The α‐diketonic moiety is formed during the last step by reductive ozonolysis of the hemiketal form of an α‐methylene trifluoromethyl ketone. Biological evaluation shows that this analogue is a weaker inducer of QS in Vibrio harveyi bacteria than DPD. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
A semi‐analytical solution for groundwater responses to stream‐stage variations and tidal fluctuations in a coastal aquifer
Authors: Kim Kue‐Young , Kim Taehee , Kim Yongje , Woo Nam‐Chil 
Published: August 2006

AbstractA two‐dimensional semi‐analytical solution to analyse stream–aquifer interactions in a coastal aquifer where groundwater level responds to tidal effects is presented. The conceptual model considered is a two‐dimensional subsurface system with stream and coastline boundaries at right angles. The dimensional and non‐dimensional boundary value problems were solved for water level in the aquifer by successive application of Laplace and Fourier transform techniques, and the results were obtained by numerical inversion of the transformed solution. The solution was then verified by reducing the solutions to one‐dimensional known problems and comparing the results with those from previous studies. Hypothetical examples were used to examine the characteristics of water‐level variations due to the variations in stream stage and the fluctuations in tide level. Sensitivity analysis indicated that streambed leakance has no influence over the amplitude of groundwater fluctuations, but that the effect of stream stage increases with increasing leakance. Little difference was observed in the water level for different aquifer penetration ratios with narrow stream width. Increases in streambed leakance caused increases in the effect of aquifer penetration by the stream on the water level. An increased specific yield value resulted in decreased amplitude of water fluctuations and mean water level, and showed that water‐level variations due to stream and tidal boundaries are sensitive to specific yield. Copyright © 2006 John Wiley & Sons, Ltd.
The interaction between a manmade lake and groundwater: an example site in the Aurku area, Chiayi County, Taiwan
Authors: Ting Cheh‐Shyh , Jean Jiin‐Shuh , Tseng Chien‐Chang , Wu Ming‐Chee 
Published: August 2006

AbstractThe objectives of this study are (1) to understand the subsurface hydrology in the Aurku area, Chiayi County, southern Taiwan, and (2) to determine the interaction between the manmade lake and groundwater level through the recharge produced by infiltration by on‐site investigation and laboratory sand tank simulation. The manmade lake was selected as the field site for groundwater recharge effect so as to assess the role of infiltration from the aquaculture ponds in this area. These results can be used as reference for future application of constructing a series of manmade lakes. The field experiment was performed to measure the infiltration rate of the manmade lake by using the water balance method and double‐ring infiltration test. The results demonstrated that the manmade lake had helped the recharge of the groundwater. Raising or maintaining a higher water level of the manmade lake can promote higher infiltration. When the groundwater level is equal to or higher than the bottom of the manmade lake, infiltration will slow or cease. The field experiment and laboratory sand tank simulation demonstrated that the infiltration rate increased with the higher storage depth of the manmade lake. The laboratory simulation also indicated that while the groundwater level was lower than the bottom of manmade lake (i.e. the reference level) and the initial water depth (3 cm) was equal to or greater than 50% of the full water storage depth, the infiltration depth increased with time. However, the infiltration depth would be very small or nearly zero when the groundwater level was higher than the bottom of the manmade lake. Copyright © 2006 John Wiley & Sons, Ltd.
Ab initio QM/MM dynamics of H3O+ in water
Authors: Intharathep Pathumwadee , Tongraar Anan , Sagarik Kritsana 
Published: August 2006

AbstractA molecular dynamics (MD) simulation based on a combined ab initio quantum mechanics/molecular mechanics (QM/MM) method has been performed to investigate the solvation structure and dynamics of H3O+ in water. The QM region is a sphere around the central H3O+ ion, and contains about 6–8 water molecules. It is treated at the Hartree‐Fock (HF) level, while the rest of the system is described by means of classical pair potentials. The Eigen complex (H9O) is found to be the most prevalent species in the aqueous solution, partly due to the selection scheme of the center of the QM region. The QM/MM results show that the Eigen complex frequently converts back and forth into the Zundel (H5O) structure. Besides the three nearest‐neighbor water molecules directly hydrogen‐bonded to H3O+, other neighbor waters, such as a fourth water molecule which interacts preferentially with the oxygen atom of the hydronium ion, are found occasionally near the ion. Analyses of the water exchange processes and the mean residence times of water molecules in the ion's hydration shell indicate that such next‐nearest neighbor water molecules participate in the rearrangement of the hydrogen bond network during fluctuative formation of the Zundel ion and, thus, contribute to the Grotthuss transport of the proton. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2006
Neurosteroid biosynthesis in the quail brain: a review
Authors: Tsutsui Kazuyoshi , Matsunaga Masahiro , Miyabara Hitomi , Ukena Kazuyoshi 
Published: August 2006

AbstractThe brain traditionally has been considered to be a target site of peripheral steroid hormones. In contrast to this classical concept, new findings over the past decade have shown that the brain itself also has the capability of forming steroids de novo, the so‐called “neurosteroids”. De novo neurosteroidogenesis in the brain from cholesterol is a conserved property of vertebrates. Our studies using the quail, as an excellent animal model, have demonstrated that the avian brain possesses cytochrome P450 side‐chain cleavage enzyme (P450scc), 3β‐hydroxysteroid dehydrogenase/Δ5–Δ4‐isomerase (3β‐HSD), cytochrome P450 17α‐hydroxylase/c17,20‐lyase (P45017α,lyase), 17β‐HSD, etc., and produces pregnenolone, progesterone, 3β, 5β‐tetrahydroprogesterone, androstenedione, testosterone and estradiol from cholesterol. However, the biosynthetic pathway of neurosteroids in the avian brain from cholesterol may be still incomplete, because we recently found that the quail brain actively produces 7α‐hydroxypregnenolone, a previously undescribed avian neurosteroid. This paper summarize the advances made in our understanding of biosynthesis of neurosteroids in the avian brain. J. Exp. Zool. 305A:733–742, 2006. © 2006 Wiley‐Liss, Inc.
Structures and diverse functions of frog growth hormone‐releasing peptide (fGRP) and its related peptides (fGRP‐RPs): a review
Authors: Ukena Kazuyoshi , Koda Aya , Yamamoto Kazutoshi , Iwakoshi‐ukena Eiko , Minakata Hiroyuki , Kikuyama Sakae , Tsutsui Kazuyoshi 
Published: August 2006

AbstractA new Arg–Phe–NH2 (RFamide) peptide has been discovered in the amphibian hypothalamus. The cell bodies and terminals containing this peptide were localized in the suprachiasmatic nucleus and median eminence, respectively. This peptide was further revealed to have a considerable growth hormone (GH)‐releasing activity in vitro and in vivo and hence designated as frog GH‐releasing peptide (fGRP). Molecular cloning of cDNA encoding the fGRP precursor polypeptide revealed that it encodes fGRP and its putative gene‐related peptides (fGRP‐RP‐1, ‐RP‐2, and ‐RP‐3). Subsequently, we identified these putative fGRP‐RPs as mature peptides and analyzed their hypophysiotropic activities. Only fGRP‐RP‐2 stimulated the release of GH and prolactin (PRL) in vitro and in vivo. Thus, in addition to fGRP, fGRP‐RP‐2 acts as a hypothalamic factor on the frog pituitary to stimulate the release of GH and PRL. J. Exp. Zool. 305A:815–821, 2006. © 2006 Wiley‐Liss, Inc.
Interactions of gonadotropin‐releasing hormone (GnRH) and gonadotropin‐inhibitory hormone (GnIH) in birds and mammals
Authors: Bentley George E. , Kriegsfeld Lance J. , Osugi Tomohiro , Ukena Kazuyoshi , O'brien Sara , Perfito Nicole , Moore Ignacio T. , Tsutsui Kazuyoshi , Wingfield John C. 
Published: August 2006

AbstractGonadotropin‐releasing hormone (GnRH) regulates secretion of both of the gonadotropins, luteinizing hormone (LH) and follicle‐stimulating hormone. Thus, it is a key hormone for vertebrate reproduction. GnRH was considered to be unusual among hypothalamic neuropeptides in that it appeared to have no direct antagonist, although some neurochemicals and peripheral hormones (opiates, GABA, gonadal steroids, inhibin) can modulate gonadotropin release to a degree. Five years ago, a vertebrate hypothalamic neuropeptide that inhibited pituitary gonadotropin release in a dose‐dependent manner was discovered in quail by Tsutsui et al. (2000. Biochem Biophys Res Commun 275:661–667). We now know that this inhibitory peptide, named gonadotropin‐inhibitory hormone, or GnIH, is a regulator of gonadotropin release in vitro and in vivo. Its discovery has opened the door to an entirely new line of research within the realm of reproductive biology. In our collaborative studies, we have begun to elucidate the manner in which GnIH interacts with GnRH to time release of gonadotropins and thus time reproductive activity in birds and mammals. This paper reviews the distribution of GnIH in songbirds relative to GnRHs, and our findings on its modes of action in vitro and in vivo, based on laboratory and field studies. These data are simultaneously compared with our findings in mammals, highlighting how the use of different model species within different vertebrate classes can be a useful approach to identify the conserved actions of this novel neuropeptide, along with its potential importance to vertebrate reproduction. J. Exp. Zool. 305A:807–814, 2006.© 2006 Wiley‐Liss, Inc.
Contribution of comparative fish studies to general endocrinology: structure and function of some osmoregulatory hormones
Authors: Takei Yoshio , Kawakoshi Akatsuki , Tsukada Takehiro , Yuge Shinya , Ogoshi Maho , Inoue Koji , Hyodo Susumu , Bannai Hideo , Miyano Satoru 
Published: August 2006

AbstractFish endocrinologists are commonly motivated to pursue their research driven by their own interests in these aquatic animals. However, the data obtained in fish studies not only satisfy their own interests but often contribute more generally to the studies of other vertebrates, including mammals. The life of fishes is characterized by the aquatic habitat, which demands many physiological adjustments distinct from the terrestrial life. Among them, body fluid regulation is of particular importance as the body fluids are exposed to media of varying salinities only across the thin respiratory epithelia of the gills. Endocrine systems play pivotal roles in the homeostatic control of body fluid balance. Judging from the habitat‐dependent control mechanisms, some osmoregulatory hormones of fish should have undergone functional and molecular evolution during the ecological transition to the terrestrial life. In fact, water‐regulating hormones such as vasopressin are essential for survival on the land, whereas ion‐regulating hormones such as natriuretic peptides, guanylins and adrenomedullins are diversified and exhibit more critical functions in aquatic species. In this short review, we introduce some examples illustrating how comparative fish studies contribute to general endocrinology by taking advantage of such differences between fishes and tetrapods. In a functional context, fish studies often afford a deeper understanding of the essential actions of a hormone across vertebrate taxa. Using the natriuretic peptide family as an example, we suggest that more functional studies on fishes will bring similar rewards of understanding. At the molecular level, recent establishment of genome databases in fishes and mammals brings clues to the evolutionary history of hormone molecules via a comparative genomic approach. Because of the functional and molecular diversification of ion‐regulating hormones in fishes, this approach sometimes leads to the discovery of new hormones in tetrapods as exemplified by adrenomedullin 2. J. Exp. Zool. 305A:787–798, 2006. © 2006 Wiley‐Liss, Inc.
The stanniocalcin family of proteins
Authors: Wagner Graham F. , Dimattia Gabriel E. 
Published: August 2006

AbstractStannniocalcin (STC) is a polypeptide hormone that was originally identified in bony fishes as a systemic regulator of mineral metabolism, and is best known for its regulatory effects on calcium/phosphate transport by the gills, gut and kidneys. The mammalian homolog to fish STC was discovered in 1995 and has resulted in progressively growing interest ever since as to its possible role in humans. Moreover, new discoveries in the mammalian STC field are resulting in significant reappraisals as to its role in fishes. Perhaps the most significant of these has been the discovery of a second gene encoding stanniocalcin‐related protein, or STC‐2, first in mammals and subsequently in fish. This review covers the comparative endocrinology of the STCs in fishes and mammals from the perspectives of structure, function and regulation. It then delves into some of the newer aspects of STC‐1/STC‐2 biology that have been uncovered using both classical and transgenic approaches. Of these, one of the most intriguing discoveries relates to the receptor‐mediated sequestration of STC by target cell organelles. The functions of other newly discovered mammalian and fish STC variants are also discussed, as is the recent discovery of STC‐related homologs in invertebrates. Based on our current state of knowledge, it is apparent that STC has an ancient lineage and that the STC family of proteins is proving to have significant roles in metabolism, reproduction and development. J. Exp. Zool. 305A:769–780, 2006. © 2006 Wiley‐Liss, Inc.
Temporal gene induction patterns in sheepshead minnows exposed to 17β‐estradiol
Authors: Knoebl Iris , Blum Jason L. , Hemmer Michael J. , Denslow Nancy D. 
Published: August 2006

AbstractGene arrays provide a powerful method to examine changes in gene expression in fish due to chemical exposures in the environment. In this study, we expanded an existing gene array for sheepshead minnows (Cyprinodon variegatus) (SHM) and used it to examine temporal changes in gene expression for male SHM exposed to 100 ng 17β‐estradiol (E2)/L for five time points between 0 and 48 hr. We found that in addition to the induction of genes involved in oocyte development (vitellogenin [VTG], zona radiata [ZRP]), other genes involved in metabolism and the inflammatory response are also affected. We identified five patterns of temporal induction in genes whose expression was modified due to E2 exposure. We validated the gene array data for the expression of VTG 1, VTG 2, ZRP 2 and ZRP 3 and found that with low levels of exogenous E2 (100 ng E2/L) exposure, ZRP expression precedes VTG expression. However, at higher concentrations of E2 (500 ng E2/L), the difference in temporal expression appears to be lost. Exposure to high levels of environmental contaminants may affect the normal ordered expression of genes required for reproduction. Gene expression profiling using arrays promises to be a valuable tool in the field of environmental toxicology. As more genes are identified for species used in toxicological testing, researchers will be better able to predict adverse effects to chemical exposures and to understand the relationships between changes in gene expression and changes in phenotype. J. Exp. Zool. 305A:707–719, 2006. © 2006 Wiley‐Liss, Inc.
Patterns and mechanisms of genome organization in the mouse
Authors: Graber Joel H. , Churchill Gary A. , Dipetrillo Keith J. , King Benjamin L. , Petkov Petko M. , Paigen Ken 
Published: August 2006

AbstractThe physical and functional organizations of a genome are correlated outcomes of evolution. Inbred strains of mice provide a unique opportunity for exploring these relationships, representing as they do, diverse genomes originally separated by millions of generations that were then scrambled in the laboratory and subjected to intense selection during inbreeding to homozygosity. Here we show that the resulting pattern of chromosome organization includes regional domains of functionally related elements that promote the co‐inheritance and survival of compatible sets of alleles. There are also patterns of linkage disequilibrium between domains on separate chromosomes; these are distinctly non‐random and form networks with scale‐free architecture. The strong conservation of gene order among mammals suggests that the domains and networks we find likely characterize all mammals, and possibly beyond.J. Exp. Zool. 305A:683–688, 2006. © 2006 Wiley‐Liss, Inc.
Xenobiotic detoxification in the nematode Caenorhabditis elegans
Authors: Lindblom Tim H. , Dodd Allyn K. 
Published: August 2006

AbstractThe nematode Caenorhabditis elegans is an important model organism for the study of such diverse aspects of animal physiology and behavior as embryonic development, chemoreception, and the genetic control of lifespan. Yet, even though the entire genome sequence of this organism was deposited into public databases several years ago, little is known about xenobiotic metabolism in C. elegans. In part, the paucity of detoxification information may be due to the plush life enjoyed by nematodes raised in the laboratory. In the wild, however, these animals experience a much greater array of chemical assaults. Living in the interstitial water of the soil, populations of C. elegans exhibit a boom and bust lifestyle characterized by prodigious predation of soil microbes punctuated by periods of dispersal as a non‐developing alternative larval stage. During the booming periods of population expansion, these animals almost indiscriminately consume everything in their environment including any number of compounds from other animals, microorganisms, plants, and xenobiotics. Several recent studies have identified many genes encoding sensors and enzymes these nematodes may use in their xeno‐coping strategies. Here, we will discuss these recent advances, as well as the efforts by our lab and others to utilize the genomic resources of the C. elegans system to elucidate this nematode's molecular defenses against toxins. J. Exp. Zool. 305A:720–730, 2006. © 2006 Wiley‐Liss, Inc.
A survivin‐mediated oncolytic adenovirus induces non‐apoptotic cell death in lung cancer cells and shows antitumoral potential in vivo
Authors: Li Binghua , Liu Xinran , Fan Junkai , Qi Rong , Bo Linan , Gu Jinfa , Qian Qijun , Qian Cheng , Liu Xinyuan 
Published: August 2006

AbstractBackgroundConditionally replicating adenoviruses or oncolytic adenoviruses, which can replicate selectively in tumor cells and kill them, represent an innovative class of promising cancer therapeutics. Survivin is the smallest member of the inhibitor of apoptosis (IAP) family, which is transcriptionally upregulated exclusively in most malignant tissues but not in normal tissues. It has been reported that activity of the survivin promoter is tumor‐specific, which makes the survivin promoter a good candidate to construct oncolytic viral vectors.MethodsA luciferase reporter assay was used to determine the activity of the survivin promoter in tumor and normal cells. An oncolytic adenovirus (Ad.SP/E1A) was generated by homologous recombination. The oncolytic efficacy of Ad.SP/E1A was evaluated in cell lines and in a human lung xenograft tumor mouse model.ResultsSurvivin expression was highly upregulated in tumor cells both at the protein and mRNA level. The luciferase reporter assay showed that survivin promoter activity is tumor‐specific. Ad.SP/E1A expressed E1A selectively in tumor cells and induced cytotoxicity, but not in normal cells. Moreover, in animal experiments, intratumoral administration of Ad.SP/E1A significantly suppressed the growth of xenograft tumors. Further investigation showed that Ad.SP/E1A induced cell death by an apoptosis‐independent pathway.ConclusionsAd.SP/E1A could be a potent therapeutic agent for cancer gene therapy. The investigation of the mechanisms of oncolytic virus‐induced cell death in this work will shed light on the construction of more powerful vectors for cancer therapy. Copyright © 2006 John Wiley & Sons, Ltd.
Reflections: The hospitalist movement a decade later
Authors: Wachter Robert M. 
Published: August 2006

AbstractAugust 2006 marks the 10th anniversary of the publication of an article in the New England Journal of Medicine in which Lee Goldman and I coined the term hospitalist—an event that many people characterize as the start of the hospitalist movement in the United States. The present article describes the history of those early days, highlighting some of the choices the field's initial leaders made to nurture the new specialty. In retrospect, although there were many examples of fortunate serendipity, there were also several key strategic choices, including the focus on gathering research data to demonstrate the value of the field to external stakeholders; the forceful rejection of mandatory hospitalist systems, particularly those promoted by managed care organizations; and the purposeful linking of our new field to the burgeoning movements to improve quality and patient safety in hospitals. Most of all, the field's spectacular growth and successes can be attributed to the daily work of thousands of hospitalists in clinical care, education, research, and systems improvement. These individuals have given life to our theoretical notion a decade ago that a new model for inpatient care would improve the American health care system and the care of inpatients. Journal of Hospital Medicine 2006;1:248–252. © 2006 Society of Hospital Medicine.