bluuebunny/crossref_metadata_2025_split huggingface dataset:
Facile Synthesis of Gold Nanoparticles with Narrow Size Distribution by Using AuCl or AuBr as the Precursor
Authors: Lu Xianmao , Tuan Hsing‐Yu , Korgel Brian A. , Xia Younan 
Published: December 2007

AbstractGold(I) halides, including AuCl and AuBr, were employed for the first time as precursors in the synthesis of Au nanoparticles. The synthesis was accomplished by dissolving AuI halides in chloroform in the presence of alkylamines, followed by decomposition at 60 °C. The relative low stability of the AuI halides and there derivatives eliminated the need for a reducing agent, which is usually required for AuIII‐based precursors to generate Au nanoparticles. Controlled growth of Au nanoparticles with a narrow size distribution was achieved when AuCl and oleylamine were used for the synthesis. FTIR and mass spectra revealed that a complex, [AuCl(oleylamine)], was formed through coordination between oleylamine and AuCl. Thermolysis of the complex in chloroform led to the formation of dioleylamine and Au nanoparticles. When oleylamine was replaced with octadecylamine, much larger nanoparticles were obtained due to the lower stability of [AuCl(octadecylamine)] complex relative to [AuCl(oleylamine)]. Au nanoparticles can also be prepared from AuBr through thermolysis of the [AuBr(oleylamine)] complex. Due to the oxidative etching effect caused by Br−, the nanoparticles obtained from AuBr exhibited an aspect ratio of 1.28, in contrast to 1.0 for the particles made from AuCl. Compared to the existing methods for preparing Au nanoparticles through the reduction of AuIII compounds, this new approach based on AuI halides offers great flexibility in terms of size control.
Palladium Catalysts for Highly Selective Sonogashira Reactions of Aryl and Heteroaryl Bromides
Authors: Torborg Christian , Zapf Alexander , Beller Matthias 
Published: December 2007

AbstractPalladium catalysts have been studied for the Sonogashira–Hagihara coupling of aryl and heteroaryl bromides with terminal alkynes. Among the different biarylphosphines tested, 2‐(di‐tert‐butylphosphino)‐N‐phenylindole (cataCXium PIntb) allows the efficient coupling of both activated and deactivated (hetero)aryl bromides in the presence of sodium tetrachloropalladate in tetramethylethylenediamine (TMEDA) at 80 °C. The catalyst system gives high turnover numbers (up to 14 100) and shows a broad tolerance towards functional groups such as OH and NH2, as well as heterocycles.
Expression of ERK signaling inhibitors Dusp6, Dusp7, and Dusp9 during mouse ear development
Authors: Urness Lisa D. , Li Chaoying , Wang Xiaofen , Mansour Suzanne L. 
Published: December 2007

AbstractThe levels of fibroblast growth factor (FGF) signaling play important roles in coordinating development of the mouse inner, middle, and outer ears. Extracellular signal‐regulated kinases (ERKs) are among the effectors that transduce the FGF signal to the nucleus and other cellular compartments. Attenuation of ERK activity by dephosphorylation is necessary to modulate the magnitude and duration of the FGF signal. Recently, we showed that inactivation of the ERK phosphatase, dual specificity phosphatase 6 (DUSP6), causes partially penetrant postnatal lethality, hearing loss and skeletal malformations. To determine whether other Dusps may function redundantly with Dusp6 during otic development, we surveyed the expression domains of the three ERK‐specific DUSP transcripts, Dusp6, Dusp7, and Dusp9, in the embryonic mouse ear. We show that each is expressed in partially overlapping patterns that correspond to regions of active FGF signaling, suggesting combinatorial roles in negative regulation of this pathway during ear development. Developmental Dynamics 237:163–169, 2008. © 2007 Wiley‐Liss, Inc.
Asymmetric Strecker Reaction of N‐Benzhydrylimines Utilising New Tropos Biphenyldiol‐Based Ligands
Authors: Wünnemann Stefan , Fröhlich Roland , Hoppe Dieter 
Published: December 2007

AbstractThe synthesis of a library of N‐arenesulfonyl‐1,3‐oxazolidinyl‐substituted biphenyldiols is presented. A set of two central intermediates together with easily accessible N‐arenesulfonylamino alcohols furnish a broad variety of 1,3‐oxazolidines. These are applied as chiral tropos ligands in a titanium‐mediated Strecker‐type reaction of N‐benzhydrylimines. A correlation between the ee values in the product and the diastereomeric ratio concerning the chiral axis of the ligand is made. Those substituents in the ligand which proved to lead to a higher preference for one diastereomeric conformer of the chiral axis in related compounds now provide the most selective ligands. Two privileged ligands are identified that afford superior results in 8 of 13 screenings.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Bis(diamido)‐Bridged Basket Resorcin[4]arenes as Enantioselective Receptors for Amino Acids and Amines (Eur. J. Org. Chem. 36/2007)
Authors: Botta Bruno , D'Acquarica Ilaria , Nevola Laura , Sacco Fabiola , Lopez Zara Valbuena , Zappia Giovanni , Fraschetti Caterina , Speranza Maurizio , Tafi Andrea , Caporuscio Fabiana , Letzel Matthias C. , Mattay Jochen 
Published: December 2007

AbstractThe cover picture shows two low‐energy geometries of a new bis(diamido)‐bridged basket resorcin[4]arene, which features two (1R,2R)‐(+)‐1,2‐diphenylethylenediamine bridges in its structure. The first “drops” schematically show the geometry assumed by the molecule in chloroform solution, tentatively designated as the “folded wings” structure (bottom left); the top right structure represents the geometry adopted when the solvent is removed and is named the “open wings” structure. Stochastic dynamics simulations run at 300 K, which demonstrate the irreversible conversion of the latter structure into the former one, support the “folded wings” geometry as the most likely 3D structure of the basket resorcin[4]arene in chloroform. It can be shown by FT‐ICR mass spectrometry that such a receptor can selectively accommodate the enantiomers of amino acid derivatives and amphetamine in its chiral cavity. Details are discussed in the article by B. Botta, M. Speranza et al. on p. 5995 ff. The authors thank Dr. Giovanna Cancelliere and Dr. Deborah Subissati for their contribution in designing the cover page.
The police officer's terrorist dilemma: trust resilience following fatal errors
Authors: White Mathew P. , Cohrs J. Christopher , Göritz Anja S. 
Published: December 2007

AbstractSuicide attacks have raised the stakes for officers deciding whether or not to shoot a suspect (‘Police Officer's Terrorist Dilemma’). Despite high‐profile errors we know little about how trust in the police is affected by their response to the terrorist threat. Building on a conceptualisation of lay observers as intuitive signal detection theorists, a general population sample (N = 1153) were presented with scenarios manipulated in terms of suspect status (Armed/Unarmed), officer decision (Shoot/Not Shoot) and outcome severity (e.g. suspect armed with Bomb/Knife; police shoot suspect/suspect plus child bystander). Supporting predictions, people showed higher trust in officers who made correct decisions, reflecting good discrimination ability and who decided to shoot, reflecting an ‘appropriate’ response bias given the relative costs and benefits. This latter effect was moderated by (a) outcome severity, suggesting it did not simply reflect a preference for a particular type of action, and (b) preferences for a tough stance towards terrorism indexed by Right‐Wing Authoritarianism (RWA). Despite loss of civilian life, failure to prevent minor terror attacks resulted in no loss of trust amongst people low in RWA, whereas among people high in RWA trust was positive when police erroneously shot an unarmed suspect. Relations to alternative definitions of trust and procedural justice research are discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Neuropsychiatric symptoms are associated with disability in cognitively impaired Latino elderly with and without dementia: results from the Sacramento Area Latino study on Aging
Authors: Hinton Ladson , Tomaszewski Farias Sarah , Wegelin Jacob 
Published: December 2007

AbstractObjectiveTo examine the relationship between neuropsychiatric symptoms burden and disability in cognitively impaired older Latinos.MethodsSubjects in the cross‐sectional study were 95 cognitively impaired (both demented and non‐demented) non‐institutionalized Latino elderly participating in an epidemiological cohort study and their family caregivers. Care recipient neuropsychiatric symptoms (Neuropsychiatric Inventory) and level of functional impairment (i.e. impairment in activities of daily living and instrumental activities of daily living) were assessed through interviews with family caregivers.ResultsBoth NPI total score and NPI depression subscale score were significantly associated with disability before and after controlling for potential confounding variables. The strength of the association between higher neuropsychiatric symptom levels and higher disability was similar for both the cognitively impaired not demented and demented groups.ConclusionsNeuropsychiatric symptoms are associated with increased disability in a community sample of cognitively impaired Latino elderly. More effective identification and treatment of neuropsychiatric symptoms may improve functioning in older Latinos and reduce health disparities for this population. Copyright © 2007 John Wiley & Sons, Ltd.
Lower airway humidification in spontaneously breathing tracheostomized patients: Comparative study of trachea spray versus heated humidifier
Authors: Keck Tilman , Rozsasi Ajnacska , Leiacker Richard , Scheithauer Marc Oliver 
Published: December 2007

AbstractBackground.Our aim was to compare inhalation with molecular water (vaporizing humidifier) and particulate water (trachea spray) in spontaneously breathing tracheostomized patients.Methods.We performed a randomized, 2‐way crossover study and a prospective, comparative, nonblinded study. Tracheal humidity and temperature were measured before and after use of a humidifier and spray for 1 week.Results.After both inhalation and spray, the tracheal temperature and total water content increased significantly (study 1). The temperature gradient between ambient and tracheal air was significantly higher after spray, but not after inhalation (study 2). The water gradient increased nonsignificantly after spray and inhalation. The water gradient after inhalation or spray did not differ significantly.Conclusions.Molecular water is not superior to particulate water because of temperature and humidity increase after both forms of water delivery. Because of its easy use, portability, and moisturizing effect, a trachea spray may offer additional options in postoperative tracheostomy care. © 2007 Wiley Periodicals, Inc. Head Neck, 2008
Invasive breast cancer cells exhibit increased mobility of the actin‐binding protein CapG
Authors: Renz Malte , Betz Beate , Niederacher Dieter , Bender Hans Georg , Langowski Jörg 
Published: December 2007

AbstractThe CapG protein, a Gelsolin‐related actin‐binding protein, is expressed at higher levels in breast cancer, especially in metastasizing breast cancer, than in normal breast epithelium. Furthermore, it is known that an increased expression of the CapG protein triggers an increase in cell motility. According to in vitro experiments, it was supposed that it is the nuclear fraction of the protein, which causes the increase in cell motility. Here, we examined the dynamical distribution of the CapG protein within the living cell, i.e. the import of the CapG protein into the nucleus. The nuclear import kinetics of invasive, metastasizing breast cancer cells were compared to the import kinetics of non‐neoplastic cells similar to normal breast epithelium. FRAP kinetics showed a highly significant increase in the recovery of photobleached CapG–eGFP in the cancer cells, so that a differentiation of invasive, metastasizing cells and non‐invasive, non‐metastasizing cells on the basis of transport processes of the CapG protein between the nucleus and the cytoplasm seems to be possible. Comprehension of the mobility and compartmentalization of the CapG protein in normal and in cancer cells in vivo could constitute a new basis to characterize the invasiveness and metastasizing potential of breast cancer. © 2007 Wiley‐Liss, Inc.
Aminoflavone induces oxidative DNA damage and reactive oxidative species‐mediated apoptosis in breast cancer cells
Authors: McLean Lancelot , Soto Ubaldo , Agama Keli , Francis Jawad , Jimenez Randi , Pommier Yves , Sowers Lawrence , Brantley Eileen 
Published: December 2007

AbstractAminoflavone (5‐amino‐2‐(4‐amino‐3‐fluorophenyl)‐6,8‐difluoro‐7‐methylchromen‐4‐one; AF; NSC 686288), a novel anticancer candidate agent, is undergoing clinical evaluation. AF induces DNA‐protein cross‐links (DPCs), γ‐H2AX phosphorylation, aryl hydrocarbon receptor (AhR) signaling, apoptosis and its own metabolism via cytochrome P4501A1 and 1A2 (CYP1A1/1A2) activation in sensitive estrogen receptor positive (ER+) MCF7 breast cancer cells. Estrogen receptor negative (ER−) breast cancer is typically more aggressive with a poorer prognosis. In this investigation, we evaluated the ability of AF to induce reactive oxygen species (ROS) formation, oxidative DNA damage and apoptosis in ER− MDA‐MB‐468 breast cancer cells. The antioxidant, N‐acetyl‐L‐cysteine (NAC), attenuated the cytotoxic effects of AF in MDA‐MB‐468 cells; an effect is also observed in ER+ T47D breast cancer cells. Nonmalignant MCF10A breast epithelial cells were resistant to the cytotoxic effects of AF. AF increased intracellular ROS, an effect blocked by NAC and the CYP1A1/1A2 inhibitor, α‐Naphthoflavone (α‐NF). AF induced oxidative DNA damage as evidenced by increased 8‐oxo‐7,8‐dihydroguanine (8‐oxodG) levels and DPC formation in these cells. AF caused S‐phase arrest corresponding to an increase in p21(waf1/cip1) protein expression. AF induced caspase 3, 8 and 9 activation, caspase‐dependent apoptotic body formation and poly [ADP‐ribose] polymerase (PARP) cleavage. Pretreatment with the pan‐caspase inhibitor, benzyloxycarbonyl‐Val‐Ala‐DL‐Asp(OMe)‐fluoromethylketone inhibited apoptosis and partially inhibited ROS formation and oxidative DNA damage. Pretreatment with NAC attenuated AF‐induced apoptotic body formation and caspase 3 activation. These studies suggest AF inhibits the growth of breast cancer cells in part, by inducing ROS production, oxidative DNA damage and apoptosis and has the potential to treat hormone‐independent breast cancer. © 2007 Wiley‐Liss, Inc.
A case‐control study of the association of the polymorphisms and haplotypes of DNA ligase I with lung and upper‐aerodigestive‐tract cancers
Authors: Lee Yuan‐Chin Amy , Morgenstern Hal , Greenland Sander , Tashkin Donald P. , Papp Jeanette , Sinsheimer Janet , Cao Wei , Hashibe Mia , You Nai‐Chieh Y. , Mao Jenny T. , Cozen Wendy , Mack Thomas M. , Zhang Zuo‐Feng 
Published: December 2007

AbstractTobacco smoking is a major risk factor for lung and upper‐aerodigestive‐tract (UADT) cancers. One possible mechanism for the associations may be through DNA damage pathways. DNA Ligase I (LIG1) is a DNA repair gene involved in both the nucleotide excision repair (NER) and the base excision repair (BER) pathways. We examined the association of 4 LIG1 polymorphisms with lung and UADT cancers, and their potential interactions with smoking in a population‐based case‐control study in Los Angeles County. We performed genotyping using the SNPlex method from Applied Biosystems. Logistic regression analyses of 551 lung cancer cases, 489 UADT cancer cases and 948 controls showed the expected associations of tobacco smoking with lung and UADT cancers and new associations between the LIG1 haplotypes and these cancers. For lung cancer, when compared to the most common haplotype (rs20581‐rs20580‐rs20579‐rs439132 = T‐C‐C‐A), the adjusted odds ratio (OR) is 1.2 (95% confidence limits (CL) = 0.95, 1.5) for the CACA haplotype, 1.4 (1.0, 1.9) for the CATA haplotype and 1.8 (1.1, 2.8) for the CCCG haplotype, after controlling for age, gender, race/ethnicity, education and tobacco smoking. We observed weaker associations between the LIG1 haplotypes and UADT cancers. Our findings suggest the LIG1 haplotypes may affect the risk of lung and UADT cancers. © 2007 Wiley‐Liss, Inc.
A case report: Bone marrow mesenchymal stem cells from a rett syndrome patient are prone to senescence and show a lower degree of apoptosis
Authors: Squillaro Tiziana , Hayek Giuseppe , Farina Ernesto , Cipollaro Marilena , Renieri Alessandra , Galderisi Umberto 
Published: December 2007

AbstractRett syndrome (RTT) is one of the most common genetic diseases responsible for a progressive disabling neurodevelopmental disorder. Mutations in the MeCP2 gene were identified in the great majority of RTT patients. MeCP2 protein binds to methylated DNA and produces changes in chromatin structure. This is a key event in regulation of gene expression. It has been suggested that MeCP2 might be important for neuronal development. Moreover, the frequent occurrence of osteoporosis and scoliosis in RTT patients suggests impaired bone formation and/or remodeling. Mesenchymal stem cells (MSCs) can differentiate as mesodermal cells such as bone, cartilage cells, and adipocytes. MSCs have been shown to possess great somatic plasticity; in fact, they can differentiate as neurons and astrocytes. We studied RTT patients' MSCs because they are progenitors of osteocytes, and it has been suggested that RTT patients' osteogenesis could be impaired. Moreover, MSCs might represent a useful model for the study of neurogenesis. MSCs from RTT patient showed precocious signs of senescence in a comparison with the MSCs of healthy‐patient control groups. This was in agreement with the reduced gene‐expression in the control of stem cell self‐renewal and upregulation of lineage specific genes, such as those involved in osteogenesis and neural development. Control groups enabled us to observe a lower degree of apoptosis in RTT patient cells. This means that aberrant stem/progenitor cells, instead of being eliminated, can survive and become senescent. Our research provides a new insight into RTT syndrome. Senescence phenomena could be involved in triggering RTT syndrome‐associated diseases. J. Cell. Biochem. 103: 1877–1885, 2008. © 2007 Wiley‐Liss, Inc.
Mycoplasma infection transforms normal lung cells and induces bone morphogenetic protein 2 expression by post‐transcriptional mechanisms
Authors: Jiang Shan , Zhang Shimin , Langenfeld John , Lo Shyh‐Ching , Rogers Melissa B. 
Published: December 2007

AbstractBone morphogenetic protein 2 (BMP2) is an essential growth factor and morphogen, whose pattern and level of expression profoundly influences development and physiology. We present the novel finding that mycoplasma infection induces BMP2 RNA production in six cell lines of diverse types (mesenchymal, epithelial, and myeloid). Mycoplasma infection triggered the expression of mature secreted BMP2 protein in BEAS‐2B cells (immortalized human bronchial epithelial cells), which normally do not express BMP2, and further increased BMP2 production in A549 cells (lung adenocarcinoma cells). Indeed, mycoplasma is as strong an experimental inducer as inflammatory cytokines and retinoic acid. Second, we showed that post‐transcriptional mechanisms including regulation of RNA stability, rather than transcriptional mechanisms, contributed to the increased BMP2 expression in mycoplasma‐infected cells. Furthermore, a novel G‐rich oligonucleotide, AS1411 that binds the post‐transcriptional regulator nucleolin induced BMP2 exclusively in infected cells. Finally, BMP2 stimulated proliferation in BEAS‐2B cells transformed by chronic mycoplasma infection, as demonstrated by treatment with Noggin, a BMP2 antagonist. These findings have important implications regarding the effects of mycoplasma on BMP2‐regulated processes, including cell proliferation, differentiation, and apoptosis. J. Cell. Biochem. 104: 580–594, 2008. © 2007 Wiley‐Liss, Inc.
Pregnancy in chronic renal failure: A novel cause of theca lutein cysts at MRI
Authors: Chen Eric M. , Breiman Richard S. , Sollitto Richard A. , Coakley Fergus V. 
Published: December 2007

AbstractWe describe the MRI findings of bilateral ovarian theca lutein cysts in a pregnant patient with chronic renal failure. The recognition that pregnancy in chronic renal failure may result in theca lutein cysts, presumably due to excessive serum beta human chorionic gonadotropins (hCGs) secondary to impaired renal excretion, expands the differential diagnosis for this MRI appearance, in addition to the usual considerations of gestational trophoblastic disease, multiple gestation, and ovarian hyperstimulation. J. Magn. Reson. Imaging 2007. © 2007 Wiley‐Liss, Inc.
Voxel‐based analysis of R2* maps in the healthy human brain
Authors: Péran Patrice , Hagberg Gisela , Luccichenti Giacomo , Cherubini Andrea , Brainovich Valentina , Celsis Pierre , Caltagirone Carlo , Sabatini Umberto 
Published: December 2007

AbstractPurposeTo develop a voxel‐based analysis of an R2* map of healthy human brain that is automatic, reproducible, and realizable in a single examination on a 3T MR imager. Such a tool could be useful to measure iron accumulation in neurodegenerative diseases.Materials and MethodsIn all, 18 healthy subjects underwent MR imaging at a field strength of 3T: 1) six consecutive T2*‐weighted gradient‐echo volumes were acquired using a segmented echo‐planar imaging sequence and 2) a conventional dual‐echo turbo spin echo sequence was also applied to acquire T2‐weighted images. Images were realigned and spatial correction was performed using a template brain dataset with SPM2. For each subject we performed a voxel‐by‐voxel nonlinear least‐squares fitting of the data acquired at the six echo times to obtain a monoexponential signal decay curve. The reproducibility and sensitivity to age variation were assessed by voxel‐based analysis.ResultsThe reproducibility tests in whole brain analysis showed little R2* variation. Furthermore, the statistical analysis, performed on each brain voxel, revealed a significant positive correlation between age and MR values located in regions where a slow and constant age‐related iron deposition is known.ConclusionOur method, combining data acquisition and data processing, demonstrates the feasibility of voxel‐based analysis on an R2* map and affords a high degree of sensitivity and good reproducibility while maintaining high spatial resolution. J. Magn. Reson. Imaging 2007. © 2007 Wiley‐Liss, Inc.