bluuebunny/crossref_metadata_2025_split huggingface dataset:
T-cell function is partially maintained in the absence of class IA phosphoinositide 3-kinase signaling
Authors: Deane Jonathan A. , Kharas Michael G. , Oak Jean S. , Stiles Linda N. , Luo Ji , Moore Travis I. , Ji Hong , Rommel Christian , Cantley Lewis C. , Lane Thomas E. , Fruman David A. 
Published: December 2006

AbstractThe class IA subgroup of phosphoinositide 3-kinase (PI3K) is activated downstream of antigen receptors, costimulatory molecules, and cytokine receptors on lymphocytes. Targeted deletion of individual genes for class IA regulatory subunits severely impairs the development and function of B cells but not T cells. Here we analyze conditional mutant mice in which thymocytes and T cells lack the major class IA regulatory subunits p85α, p55α, p50α, and p85β. These cells exhibit nearly complete loss of PI3K signaling downstream of the T-cell receptor (TCR) and CD28. Nevertheless, T-cell development is largely unperturbed, and peripheral T cells show only partial impairments in proliferation and cytokine production in vitro. Both genetic and pharmacologic experiments suggest that class IA PI3K signaling plays a limited role in T-cell proliferation driven by TCR/CD28 clustering. In vivo, class IA–deficient T cells provide reduced help to B cells but show normal ability to mediate antiviral immunity. Together these findings provide definitive evidence that class IA PI3K regulatory subunits are essential for a subset of T-cell functions while challenging the notion that this signaling mechanism is a critical mediator of costimulatory signals downstream of CD28.
Evolution of secretin family GPCR members in the metazoa
Authors: Cardoso João CR , Pinto Vanda C , Vieira Florbela A , Clark Melody S , Power Deborah M 
Published: December 2006

AbstractBackgroundComparative approaches using protostome and deuterostome data have greatly contributed to understanding gene function and organismal complexity. The family 2 G-protein coupled receptors (GPCRs) are one of the largest and best studied hormone and neuropeptide receptor families. They are suggested to have arisen from a single ancestral gene via duplication events. Despite the recent identification of receptor members in protostome and early deuterostome genomes, relatively little is known about their function or origin during metazoan divergence. In this study a comprehensive description of family 2 GPCR evolution is given based onin silicoand expression analyses of the invertebrate receptor genes.ResultsFamily 2 GPCR members were identified in the invertebrate genomes of the nematodesC. elegansandC. briggsae, the arthropodsD. melanogasterandA. gambiae(mosquito) and in the tunicateC.intestinalis. This suggests that they are of ancient origin and have evolved through gene/genome duplication events. Sequence comparisons and phylogenetic analyses have demonstrated that the immediate gene environment, with regard to gene content, is conserved between the protostome and deuterostome receptor genomic regions. Also that the protostome genes are more like the deuterostome Corticotrophin Releasing Factor (CRF) and Calcitonin/Calcitonin Gene-Related Peptide (CAL/CGRP) receptors members than the other family 2 GPCR members. The evolution of family 2 GPCRs in deuterostomes is characterised by acquisition of new family members, with SCT (Secretin) receptors only present in tetrapods. Gene structure is characterised by an increase in intron number with organismal complexity with the exception of the vertebrate CAL/CGRP receptors.ConclusionThe family 2 GPCR members provide a good example of gene duplication events occurring in tandem with increasing organismal complexity during metazoan evolution. The putative ancestral receptors are proposed to be more like the deuterostome CAL/CGRP and CRF receptors and this may be associated with their fundamental role in calcium regulation and the stress response, both of which are essential for survival.
Systematic identification and integrative analysis of novel genes expressed specifically or predominantly in mouse epididymis
Authors: Oh Jungsu , Lee Jiae , Woo Jong-Min , Choi Eunyoung , Park Inju , Han Cecil , Baek Namhoe , Lee Hoyong , Kim Do Han , Cho Chunghee 
Published: December 2006

AbstractBackgroundMaturation of spermatozoa, including development of motility and the ability to fertilize the oocyte, occurs during transit through the microenvironment of the epididymis. Comprehensive understanding of sperm maturation requires identification and characterization of unique genes expressed in the epididymis.ResultsWe systematically identified 32 novel genes with epididymis-specific or -predominant expression in the mouse epididymis UniGene library, containing 1505 gene-oriented transcript clusters, byin silicoandin vitroanalyses. The Northern blot analysis revealed various characteristics of the genes at the transcript level, such as expression level, size and the presence of isoform. We found that expression of the half of the genes is regulated by androgens. Further expression analyses demonstrated that the novel genes are region-specific and developmentally regulated. Computational analysis showed that 15 of the genes lack human orthologues, suggesting their implication in male reproduction unique to the mouse. A number of the novel genes are putative epididymal protease inhibitors or β-defensins. We also found that six of the genes have secretory activity, indicating that they may interact with sperm and have functional roles in sperm maturation.ConclusionWe identified and characterized 32 novel epididymis-specific or -predominant genes by an integrative approach. Our study is unique in the aspect of systematic identification of novel epididymal genes and should be a firm basis for future investigation into molecular mechanisms underlying sperm maturation in the epididymis.
Over-diagnosis of malaria is not a lost cause
Authors: Masika Paul M , Semarundu Waziri J , Urassa Raymond , Mosha Jackline , Chandramohan Daniel , Gosling Roly D 
Published: December 2006

Abstract

Background
Recent studies have highlighted the over-diagnosis of malaria in clinical settings in Africa. This study assessed the impact of a training programme implemented as part of an intervention trial on diagnostic behaviour of clinicians in a rural district hospital in a low-moderate malaria transmission setting.

Methods
From the beginning of 2005, a randomized controlled trial (RCT) of intermittent preventive treatment for malaria in infants (IPTi) has been conducted at the study hospital. As part of the RCT, the study team offered laboratory quality assurance, and supervision and training of paediatric ward staff using information on malaria epidemiology in the community. Data on clinical and blood slide confirmed cases of malaria from 2001 to 2005 were extracted from the hospital records.

Results
The proportion of blood slides positive for malaria parasites had decreased from 21% in 2001 to 7% in 2005 (p < .01). The proportion of outpatient and inpatient cases diagnosed as malaria ranged between 34% and 28% from 2001 to 2004 and this decreased substantially to 17% after the introduction of the package of training and support in 2005 (p < .01). There was no clear trend in the ratio of blood slide examined versus total diagnosis of malaria.

Conclusion
It may be possible to change the diagnostic behaviour of clinicians by rigorous training using local malaria epidemiology data and supportive supervision.
Neuroendocrine Phenotype Analysis in Five Patients with Isolated Hypogonadotropic Hypogonadism due to a L102P Inactivating Mutation of GPR54
Authors: Tenenbaum-Rakover Yardena , Commenges-Ducos Monique , Iovane André , Aumas Chantal , Admoni Osnat , de Roux Nicolas 
Published: December 2006

Abstract
Context: Loss of function of the G protein-coupled receptor of kisspeptins (GPR54) was recently described as a new cause of isolated hypogonadotropic hypogonadism. In vivo studies performed in several species have confirmed the major role of kisspeptins in neuroendocrine regulation of the gonadotropic axis and therefore sexual maturation.
Objective: The objective of this study was to specify the exact contribution of kisspeptins and GPR54 to the initiation of puberty in humans.
Design: Detailed neuroendocrine descriptions were performed in five patients with isolated hypogonadotropic hypogonadism bearing a new GPR54-inactivating mutation.
Results: A homozygous mutation (T305C) leading to a leucine substitution with proline (L102P) was found in the five affected patients. This substitution completely inhibited GPR54 signaling. Phenotypic analysis revealed variable expressivity in the same family, either partial or complete gonadotropic deficiency. LH pulsatility analysis showed peaks with normal frequency but low amplitude. Repeated GnRH tests performed between 12 and 21 yr of age in one affected male revealed progressive changes in pituitary response from an early pubertal to an almost full pubertal pattern. Double GnRH test stimulations performed at a 120-min interval showed reduced dynamic pituitary response in GPR54-mutated patients.
Conclusion: GPR54 inactivation does not impede neuroendocrine onset of puberty; rather, it delays and slows down pubertal maturation of the gonadotropic axis. The L102P loss of function mutation in GPR54 results in a more quantitative than qualitative defect of gonadotropic axis activation.
Tuning of Electronic Structures of Quasi-One-Dimensional Halogen-Bridged Ni–Pd Mixed-Metal Complexes, [Ni1−xPdx(chxn)2X]X2 (X = Cl, Br) with Strong Electron Correlation
Authors: Yamashita Masahiro , Takaishi Shinya 
Published: December 2006

Abstract
This article describes the tuning of the electronic structures in a series of quasi-one-dimensional halogen-bridged Ni–Pd mixed-metal complexes, [Ni1−xPdx(chxn)2X]X2 (chxn = 1R,2R-diaminocyclohexane; X, Y = Cl or Br). In these compounds, planar [M(chxn)2] units are bridged by halogen ions (X), forming linear chain M–X–M structures. Therefore, their electronic structures are 1D and are composed of hybridization between the dz2 orbitals of the metal ions and pz orbitals of the bridging halogens. In this system, electron-correlation on the Ni sites and electron–phonon interaction on the Pd sites should compete with each other. Their electronic structures have been investigated by means of the single-crystal reflectance, ESR and IR spectroscopies, electrical conductivities, and X-ray diffuse scattering. Moreover, their local electronic structures have been directly observed by scanning tunneling microscopy (STM) using single-crystals at room temperature and under ambient pressure. As a result, while the oxidation state of the Ni sites is +3 in all mixing ratios in these compounds due to strong electron-correlation, the conversion from the PdIII Mott–Hubbard states to the PdII–PdIV mixed-valence states is observed around x ≈ 0.90 for Br and x ≈ 0.85 for Cl. Interestingly, the spin-soliton in Ni0.05Pd0.95(chxn)2Br3 was directly observed by STM for the first time.
Photoinduced Charge-Separation and Charge-Recombination Processes of Oligo(thienyleneethynyl)–Fullerene Dyad Molecules
Authors: Fujitsuka Mamoru , Makinoshima Takashi , Takamizawa Atushi , Araki Yasuyuki , Ito Osamu , Obara Yuko , Aso Yoshio , Otsubo Tetsuo 
Published: December 2006

Abstract
Photoinduced charge-separation and -recombination processes in two series of oligo(thienyleneethynyl)–fullerene dyads (abbreviated as nTE–C60), in which the nTE moiety has a linear (nαTE) or zigzag structure (nβTE), have been investigated by using transient absorption spectroscopy with sub-picosecond laser flash photolysis. Based on the transient absorption spectra, charge separation occurs in nTE–C60 with the rate constants on the order of 1011 s−1, indicating almost quantitative charge separation. For all nTE–C60 dyads, the charge-separation rate-constants in toluene were larger than those in benzonitrile, suggesting that the charge-separation process is a solvent-controlled adiabatic process. On the other hand, the charge-recombination processes going back to the ground state occurred with the rate constants on the order of 108–109 s−1. The charge-recombination rate of nαTE–C60 was faster than that in nβTE–C60 with a zigzag structure, in spite of similar free energy change for the charge recombination.
Geometrical Isomerism and Stability of Mono- and Dichalcogenide Analogs of Carbamic Acid H2NC(=X)YH (X, Y = O, S, Se)
Authors: Kaur Damanjit , Kaur Rupinder Preet , Kaur Pushwinder 
Published: December 2006

Abstract
Activation barriers for geometrical isomerism and tautomerization have been studied for carbamic acid and its mono- and dichalcogenide analogs at B3LYP/6-31+G*, MP2/6-31+G*, and G2MP2 theoretical levels. The studies indicate that carbamic acid with higher chalcogen prefers chalcogen at the chalcogenol position. Proton affinities, gas-phase acidities and atomic charges for these molecules have also been evaluated. Unimolecular, bimolecular, and two-step pathways for the decomposition of carbamic acid and its analogs are also analyzed, from which it was concluded that the two step mechanism is the more plausible pathway.
Effects of Micelles on the Complex Formation of [PtCl(dien)]+ with Biologically Relevant Ligands
Authors: Soldatovic Tanja , Vasic Vesna , Bugarcic Zivadin D 
Published: December 2006

Abstract
Substitution reactions of [PtCl(dien)]+ (dien = diethylenetriamine) with some biologically relevant ligands, such as l-methionine ((l)-Met), glutathione (GSH), and guanosine 5′-monophosphate (5′-GMP), were studied in aqueous 0.10, 0.05, and 0.01 M NaClO4 solutions at pH 2.5 using UV–vis spectrophotometry. The kinetics and mechanism of the complex-formation reactions were studied as a function of nucleophile concentration and temperature. These reactions were also studied in the presence and absence of micelles of sodium dodecyl sulfate (SDS). The presence of anionic micelles accelerated complex-formation. The largest effect of micelles has been observed in the case of l-methionine. On the other hand, an increase in the ionic strength in the presence of micelles caused a decrease in the rate. The negative entropies of activation support an associative complex-formation mechanism.
Exciplex Formation of Intermolecularly Hydrogen-Bonded System between Anthracene and N,N-Dimethylaniline Derivatives
Authors: Ohshiro Ikuma , Ikegami Masashi , Nishimura Yoshinobu , Arai Tatsuo 
Published: December 2006

Abstract
We prepared 2-ureido-4(1H)-pyrimidinone (UPy) derivatives bearing anthracene (AN) and N,N-dimethylaniline (DMA) connected by various lengths (n) of methylene chains (UPyAN, UPyDMAn) to examine the electron-transfer dynamics between the excited state of UPyAN and the ground state of UPyDMAn by spectroscopy. UPyAN and UPyDMAn formed quadruple hydrogen bonds and exhibited exciplex emission between AN and DMA chromophores. From the fluorescence lifetime measurement, the lifetime of exciplex emission increased from 38 to 64 ns with increasing n. The quenching process of singlet excited UPyAN by UPyDMAn is proposed to be different from that of methylene-linked dimethylaniline and anthracene. Furthermore, the results indicate that both AN and DMA keep almost constant distance regardless of n of UPyDMAn. DMA was considered to be located near a quadruple hydrogen-bonding region in the excited state, while deactivation process of exciplex was independent of n, which may be characteristic of a hydrogen-bonded system.
Ruthenium-Catalyzed Addition of Terminal Alkynes to Alkynylstannanes with Migration of the Stannyl Group
Authors: Shirakawa Eiji , Nakayama Kouji , Morita Ryotaro , Tsuchimoto Teruhisa , Kawakami Yusuke , Matsubara Toshiaki 
Published: December 2006

Abstract
In the presence of a catalytic amount of a ruthenium complex coordinated with PBu3, alkynylstannanes (R1C≡CSnBu3) were found to accept the addition of terminal alkynes (R2C≡CH) with a 1,2-shift of the stannyl group to give (E)- and (Z)-1-tributylstannylbut-1-en-3-ynes (Bu3SnC(R1)=CHC≡CR2). Various combinations of substrates having an aromatic and/or aliphatic substituent can be used, and the stereochemical outcome depends largely on the character of these substituents. The reaction of aliphatic terminal alkynes proceeds stereoselectively, and substituent R1 on the alkynylstannanes determines the configuration: E for R1 = alkyl and Z for R1 = aryl. In contrast, the reaction of arylacetylenes gave a mixture of stereoisomers irrespective of the character of substituent R1 on the alkynylstannane. Ruthenium–β-stannylvinylidene complexes generated from a ruthenium complex and an alkynylstannane with migration of the stannyl group are likely to be key intermediates, which accept addition of the C–H bond of terminal alkynes to give the corresponding stannylenynes. DFT calculation clearly shows that the 1,2-shift of the stannyl group on formation of ruthenium–β-stannylvinylidene complexes is more facile than the corresponding 1,2-hydrogen shift of the coordinating terminal alkynes. The effect of the substituents on the stereoselectivity also is discussed based on the calculation.
Synthesis of 4-Aryl-2-sulfenyl-2H-1-benzothiopyran Derivatives by Cyclization of [2-(1-Aryl-2-methoxyvinyl)phenylthio][methyl(or phenyl)thio]methyllithiums
Authors: Kobayashi Kazuhiro , Horiuchi Mai , Miyamoto Kazuna , Morikawa Osamu , Konishi Hisatoshi 
Published: December 2006

Abstract
4-Aryl-2-methyl(or phenyl)thio-2H-1-benzothiopyrans have been prepared in satisfactory yields from the corresponding 1-(1-aryl-2-methoxyethenyl)-2-{[methyl(or phenyl)thiomethyl]thio}benzenes via lithiation of the carbon atom between the two sulfur atoms, followed by intramolecular cyclization with loss of lithium methoxide.
Microstructure of HDTMA+-Modified Montmorillonite and its Influence on Sorption Characteristics
Authors: He Hongping , Zhou Qin , Martens Wayde N. , Kloprogge Theo J. , Yuan Peng , Xi Yunfei , Zhu Jianxi , Frost Ray L. 
Published: December 2006

AbstractA series of organoclays with monolayers, bilayers, pseudotrilayers, paraffin monolayers and paraffin bilayers were prepared from montmorillonite by ion exchange with hexadecyltrimethylammonium bromide (HDTMAB). The HDTMAB concentrations used for preparing the organoclays were 0.5, 0.7, 1.0, 1.5, 2.0 and 2.5 times the montmorillonite cation exchange capacity (CEC). The microstructural parameters, including the BET-N2 surface area, pore volume, pore size, and surfactant loading and distribution, were determined by X-ray diffraction, N2 adsorption-desorption and high-resolution thermogravimetric analysis (HRTG). The BET-N2 surface area decreased from 55 to 1 m2/g and the pore volume decreased from 0.11 to 0.01 cm3/g as surfactant loading was increased from Na-Mt to 2.5CEC-Mt. The average pore diameter increased from 6.8 to 16.3 nm as surfactant loading was increased. After modifying montmorillonite with HDTMAB, two basic organoclay models were proposed on the basis of HRTG results: (1) the surfactant mainly occupied the clay interlayer space (0.5CEC-Mt, 0.7CEC-Mt, 1.0CEC-Mt); and (2) both the clay interlayer space and external surface (1.5CEC-Mt, 2.0CEC-Mt, 2.5CEC-Mt) were modified by surfactant. In model 1, the sorption mechanism of p-nitrophenol to the organoclay at a relatively low concentration involved both surface adsorption and partitioning, whereas, in model 2 it mainly involved only partitioning. This study demonstrates that the distribution of adsorbed surfactant and the arrangement of adsorbed HDTMA+ within the clay interlayer space control the efficiency and mechanism of sorption by the organoclay rather than BET-N2 surface area, pore volume, and pore diameter.
Molecular detection of tyrosinase transcripts in peripheral blood from patients with malignant melanoma: correlation of PCR sensitivity threshold with clinical and pathologic disease characteristics
Authors: Mitropapas Georgios , Nezos Andrianos , Halapas Antonis , Pissimissis Nikolaos , Lembessis Peter , Sourla Antigone , Vassilopoulos Pericles , Koutsilieris Michael 
Published: December 2006

AbstractClin Chem Lab Med 2006;44:1403–9.
Combining markers of nephrotoxicity and hepatotoxicity for improved monitoring and detection of chronic alcohol abuse
Authors: Taracha Ewa , Habrat Bogusław , Chrapusta Stanisław J. , Lehner Małgorzata , Wisłowska Aleksandra , Woronowicz Bohdan T. , Bogulas Marta , Charewicz Jolanta , Markuszewski Cezary , Płaźnik Adam 
Published: December 2006

AbstractClin Chem Lab Med 2006;44:1446–52.
Mapping the Boosterist Imaginary: Colonial Williamsburg, Historical Tourism, and the Construction of Managerial Memory
Authors: MILLER JAMES S. 
Published: December 2006

Abstract
With very few exceptions, existing scholarship on public memory in America has tended to script commercial-industrial “development” as the implacable adversary of legitimate collective remembering. Indeed, it has become a virtual article of faith that any attempt at commercially underwritten historical reconstruction involves, by definition, an act of historical falsification. This essay sets about to revise this longstanding conceit by pondering some of the specific ways that industrial and commercial development practices came during the early twentieth century to be imagined as technologies for producing new and viable models of a specifically white-collar history. To make this argument, I focus on the phenomenon of historical tourism, a movement that gained popularity in the 1920s and 30s (typified by such ventures as Henry Ford's Greenfield Village and John D. Rockefeller's Colonial Williamsburg), which dedicated itself to reconstructing vestiges of America's “bygone” past. Using Colonial Williamsburg as my case study, I explore how the planners and promoters behind this movement forged a discourse of historical reconstruction designed to make the tactics of industrial-commercial development compatible with the vaunted ideals of historical recovery and cultural conservation. More specifically, I show how this discourse labored to imagine the past itself as a useful and fungible resource: a raw material to be taken up, managed, and improved by the agents of the modern corporate-capitalist order.