bluuebunny/crossref_metadata_2025_split huggingface dataset:
Siliceous Mesocellular Foam‐Supported Aza(bisoxazoline)‐Copper Catalysts
Authors: Lim Jaehong , Riduan Siti Nurhanna , Lee Su Seong , Ying Jackie Y. 
Published: May 2008

AbstractAza(bisoxazoline) was easily immobilized on siliceous mesocellular foam (MCF) in a systematic approach. It was found that silanol precapping, linker group flexibility, ligand loading, and silanol postcapping were important factors to consider in optimizing silica‐supported aza(bisoxazoline) catalysts. The optimized MCF‐supported aza(bisoxazoline)‐copper catalyst offered the same enantioselectivity as its homogeneous counterpart, and excellent recyclability. The heterogenized catalyst showed a much higher chemoselectivity in a short reaction time. The heterogenized aza(bisoxazoline)‐copper(I) catalyst was successfully applied to a circulating flow‐type packed bed reactor with excellent productivity and enantioselectivity. The circulating flow‐type reactor was found to be very useful for gas‐generating catalytic reactions such as cyclopropanation reaction.
PdAlqEn: A Novel Upgraded Version of the PdEnCatTM Family of Polyurea Encapsulated Catalysts
Authors: Toubiana Judith , Chidambaram Mandan , Santo Asaf , Sasson Yoel 
Published: May 2008

AbstractPalladium nanoparticles are stabilized and encapsulated in a combination of polyurea and an ionic liquid (Aliquat 336) to obtain the PdAlqEn hybrid catalyst. The novel composite material is applied as a recyclable and robust catalyst in hydrogenation reactions.
Gallium Trichloride‐Promoted Ethynylation Reaction of 1,4‐Dienes
Authors: Nishimura Yoshio , Kiryu Masato , Suwa Katsunori , Amemiya Ryo , Yamaguchi Masahiko 
Published: May 2008

AbstractCyclopentadienes and silylated 1,4‐dienes were deprotonated with gallium trichloride (GaCl3), and the resultant pentadienylgalliums underwent an ethynylation reaction with chlorosilylethyne. The silyl substituent on the olefin had an effect to increase the acidity of the allylic protons.
Extreme phenotypic diversity and nonpenetrance in families with the LMNA gene mutation R644C
Authors: Rankin Julia , Auer‐Grumbach Michaela , Bagg Warwick , Colclough Kevin , Duong Nguyen Thuy , Fenton‐May Jane , Hattersley Andrew , Hudson Judith , Jardine Philip , Josifova Dragana , Longman Cheryl , McWilliam Robert , Owen Katharine , Walker Mark , Wehnert Manfred , Ellard Sian 
Published: May 2008

AbstractMutations in the LMNA gene result in diverse phenotypes including Emery Dreifuss muscular dystrophy, limb girdle muscular dystrophy, dilated cardiomyopathy with conduction system disease, Dunnigan type familial partial lipodystrophy, mandibulo acral dysplasia, Hutchinson Gilford progeria syndrome, restrictive dermopathy and autosomal recessive Charcot Marie Tooth type 2. The c.1930C > T (R644C) missense mutation has previously been reported in eight unrelated patients with variable features including left ventricular hypertrophy, limb girdle muscle weakness, dilated cardiomyopathy and atypical progeria. Here we report on the details of nine additional patients in eight families with this mutation. Patients 1 and 2 presented with lipodystrophy and insulin resistance, Patient 1 having in addition focal segmental glomerulosclerosis. Patient 3 presented with motor neuropathy, Patient 4 with arthrogryposis and dilated cardiomyopathy with left ventricular non‐compaction, Patient 5 with severe scoliosis and contractures, Patient 6 with limb girdle weakness and Patient 7 with hepatic steatosis and insulin resistance. Patients 8 and 9 are brothers with proximal weakness and contractures. Nonpenetrance was observed frequently in first degree relatives. This report provides further evidence of the extreme phenotypic diversity and low penetrance associated with the R644C mutation. Possible explanations for these observations are discussed. © 2008 Wiley‐Liss, Inc.
Partial growth hormone deficiency and changed bone quality and mass in type I trichorhinophalangeal syndrome
Authors: Stagi Stefano , Bindi Giuseppe , Galluzzi Fiorella , Lapi Elisabetta , Salti Roberto , Chiarelli Francesco 
Published: May 2008

AbstractThe trichorhinophalangeal syndromes (TRPSs) are syndromes due to haploinsufficiency of genes in the chromosome 8q24.12 region. Type I TRPS is characterized by typical facial features including sparse, brittle and fine hair, bulbous nose, and a long philtrum, as well as skeletal abnormalities. Growth retardation is a feature frequently found in these patients, who commonly are of short stature; however, only one case with growth hormone deficiency has been described in a TRPS patient and that patient had type II TRPS. Skeletal morphological abnormalities have been studied, but investigation of bone metabolism and quality in this kind of patients are not available. In this report we describe two cases of type I TRPS with partial growth hormone deficiency and significant bone mass and quality impairment, which was unresponsive to GH treatment. © 2008 Wiley‐Liss, Inc.
When good transcripts go bad: artifactual RT‐PCR ‘splicing’ and genome analysis
Authors: Roy Scott William , Irimia Manuel 
Published: May 2008

AbstractGene and intron prediction are essential for accurate inferences about genome evolution. Recently, two genome‐wide studies searched for recent intron gains in humans, reaching very different conclusions: either of a complete absence of intron gain since early mammalian evolution, or of creation of numerous introns by genomic duplication in repetitive regions. We discuss one possible explanation: the underappreciated phenomenon of “template switching”, by which reverse transcriptase may create artifactual splicing‐like events in the preparation of cDNA/EST libraries, may cause complications in searches for newly gained introns in repetitive regions. We report large numbers of apparent template switching in transcript sequences from the intron‐poor protists Trichomonas vaginalis and Giardia lamblia. Supplementary material for this article can be found on the BioEssays website (http://www.interscience.wiley.com/jpages/0265‐9247/suppmat/index.html). BioEssays 30:601–605, 2008. © 2008 Wiley Periodicals, Inc.
Cell divisions and mammalian aging: integrative biology insights from genes that regulate longevity
Authors: de Magalhães João Pedro , Faragher Richard G.A. 
Published: May 2008

AbstractDespite recent progress in the identification of genes that regulate longevity, aging remains a mysterious process. One influential hypothesis is the idea that the potential for cell division and replacement are important factors in aging. In this work, we review and discuss this perspective in the context of interventions in mammals that appear to accelerate or retard aging. Rather than focus on molecular mechanisms, we interpret results from an integrative biology perspective of how gene products affect cellular functions, which in turn impact on tissues and organisms. We review evidence suggesting that mutations that give rise to features resembling premature aging tend to be associated with cellular phenotypes such as increased apoptosis or premature replicative senescence. In contrast, many interventions in mice that extend lifespan and might delay aging, including caloric restriction, tend to either hinder apoptosis or result in smaller animals and thus may be the product of fewer cell divisions. Therefore, it appears plausible that changes in the number of times that cells, and particularly stem cells, divide during an organism's lifespan influence longevity and aging. We discuss possible mechanisms related to this hypothesis and propose experimental paradigms. BioEssays 30:567–578, 2008. © 2008 Wiley Periodicals, Inc.
Reconstructing evolution: Gene transfer from plastids to the nucleus
Authors: Bock Ralph , Timmis Jeremy N. 
Published: May 2008

AbstractDuring evolution, the genomes of eukaryotic cells have undergone major restructuring to meet the new regulatory challenges associated with compartmentalization of the genetic material in the nucleus and the organelles acquired by endosymbiosis (mitochondria and plastids). Restructuring involved the loss of dispensable or redundant genes and the massive translocation of genes from the ancestral organelles to the nucleus. Genomics and bioinformatic data suggest that the process of DNA transfer from organelles to the nucleus still continues, providing raw material for evolutionary tinkering in the nuclear genome. Recent reconstruction of these events in the laboratory has provided a unique tool to observe genome evolution in real time and to study the molecular mechanisms by which plastid genes are converted into functional nuclear genes. Here, we summarize current knowledge about plastid‐to‐nuclear gene transfer in the context of genome evolution and discuss new insights gained from experiments that recapitulate endosymbiotic gene transfer in the laboratory. BioEssays 30:556–566, 2008. © 2008 Wiley Periodicals, Inc.
Modeling the circadian clock: From molecular mechanism to physiological disorders
Authors: Leloup Jean‐Christophe , Goldbeter Albert 
Published: May 2008

AbstractBased on genetic and biochemical advances on the molecular mechanism of circadian rhythms, a computational model for the mammalian circadian clock is used to examine the dynamical bases of circadian‐clock‐related physiological disorders in humans. Entrainment by the light–dark cycle with a phase advance or a phase delay is associated with the Familial advanced sleep phase syndrome (FASPS) or the Delayed sleep phase syndrome (DSPS), respectively. Lack of entrainment corresponding to the occurrence of quasiperiodic oscillations with or without phase jump can be associated with the non‐24 h sleep–wake syndrome. In the close vicinity of the entrainment domain, the model uncovers the possibility of infradian oscillations of very long period. Perturbation in the form of chronic jet lag, as used in mice, prevents entrainment of the circadian clock and results in chaotic or quasiperiodic oscillations. It is important to clarify the conditions for entrainment and for its failure because dysfunctions of the circadian clock may lead to physiological disorders, which pertain not only to the sleep–wake cycle but also to mood and cancer. BioEssays 30:590–600, 2008. © 2008 Wiley Periodicals, Inc.
Control of epithelial cell structure and developmental fate: Lessons from Helicobacter pylori
Authors: Mimuro Hitomi , Berg Douglas E. , Sasakawa Chihiro 
Published: May 2008

AbstractValuable insights into eukaryotic regulatory circuits can emerge from studying interactions of bacterial pathogens such as Helicobacter pylori with host tissues. H. pylori uses a type IV secretion system (T4SS) to deliver its CagA virulence protein to epithelial cells, where much of it becomes phosphorylated. CagA's phosphorylated and non‐phosphorylated forms each interact with host regulatory proteins to alter cell structure and cell fate. Kwok and colleagues1 showed that CagA destined for phosphorylation is delivered using host integrin as receptor and H. pylori's CagL protein as an integrin‐specific adhesin, and that CagL–integrin‐binding activates the kinase cascade responsible for CagA phosphorylation. This research contributes to understanding infectious disease and the control of cell fates. BioEssays 30:515–520, 2008. © 2008 Wiley Periodicals, Inc.
α‐Lactosylceramide as a Novel “Sugar‐Capped” CD1d Ligand for Natural Killer T Cells: Biased Cytokine Profile and Therapeutic Activities
Authors: Zhang Wenpeng , Zheng Xincheng , Xia Chengfeng , Perali Ramu Sridhar , Yao Qingjia , Liu Yang , Zheng Pan , Wang Peng George 
Published: May 2008

AbstractThe invariant natural killer T cells (iNKT) cells have emerged as an important regulator of immunity to infection, cancer, and autoimmune diseases. They can be activated by glycolipids that bind to CD1d. The most effective iNKT ligand reported to date is α‐galactosylceramide (α‐GalCer), which stimulates iNKT cells to secrete both Th‐1 and Th‐2 cytokines. Indiscriminate induction of both types of cytokines could limit the therapeutic potential of iNKT ligands, as Th‐1 and Th‐2 cytokines play different roles under physiological and pathological conditions. Therefore, a ligand with a biased cytokine‐release profile would be highly desirable. Here, we report the synthesis and biological activity of α‐lactosylceramide (α‐LacCer). Our data demonstrate that α‐LacCer can stimulate iNKT cells to proliferate and release cytokines, both in vitro and in vivo. Interestingly, while α‐LacCer is approximately 1000‐times less efficient than α‐GalCer in inducing Th‐1 cytokines, it is as potent as α‐GalCer in the induction of Th‐2 cytokines; therefore, α‐LacCer is a novel compound that induces a biased cytokine release. Processing by β‐glycosidase was critical for α‐LacCer activity. Moreover, in vivo experiments suggest that α‐LacCer is at least as potent as α‐GalCer in the treatment of tumors and experimental autoimmune encephalomyelitis.
Generation of an Aromatic Amide‐Derived Phosphane (Aphos) Library by Self‐Assisted Molecular Editing and Applications of Aphos in Room‐Temperature Suzuki–Miyaura Reactions
Authors: Dai Wei‐Min , Li Yannian , Zhang Ye , Yue Congyong , Wu Jinlong 
Published: May 2008

AbstractAromatic amide‐derived phosphanes (Aphos) are hemilabile P,O‐coordinating ligands, which, when combined with a Pd precursor, yield a promising precatalyst system for Suzuki–Miyaura cross‐coupling reactions. A focused library of Aphos ligands has been constructed for structural optimization, with the target of improving catalytic efficacy. By using microwave irradiation at accurately regulated temperature, an expeditious and reproducible one‐pot synthesis and screening protocol was designed and experimentally validated. The success is based on a unique self‐assisted molecular editing (SAME) process in which both the substrate and the product molecules catalyze formation of the product. Thus, starting from a 4‐chlorobenzamide‐derived Aphos as the substrate, parallel reactions with a selected set of arylboronic acids, in the absence of an added external phosphane ligand to Pd, produced a family of structurally edited Aphos ligands. The resultant reaction mixture containing the new Aphos, the Pd species, and the base could be used for in situ screening of the Aphos efficacy in a reference Suzuki–Miyaura coupling reaction. The structures of all Aphos ligands were characterized by 31P NMR spectroscopy and their catalytic profiles in the reference reaction were evaluated by HPLC analysis. These data allowed the identification of an efficient Aphos ligand, capable of promoting room‐temperature Suzuki–Miyaura coupling of unactivated and sterically hindered aryl chlorides with arylboronic acids under mildly basic conditions.
Fine needle aspiration of head and neck masses in the operating room: Accuracy and potential benefits
Authors: Arabi Haitham , Yousef Nida , Bandyopadhyay Sudeshna , Feng Jining , Yoo George H. , Al‐Abbadi Mousa A. 
Published: May 2008

AbstractFine needle aspiration (FNA) in the operating room is a convenient optional diagnostic approach. Our objective of this study was to evaluate the accuracy and study the potential benefits of fine needle aspiration in the operating room.Retrospective review of all intraoperative FNA that were requested and performed by pathologists over 20‐month period was carried out. Immediate smears were interpreted by the cytopathology team after staining with Diff Quik stain. All cases were reviewed and correlation with subsequent tissue diagnosis was done. Accuracy was calculated and potential benefits were discussed. The number of aspirates was 32. Adequate material for immediate and final interpretation was achieved in 31 cases (sensitivity 97%). In 20 cases (63%), malignancy was diagnosed while a benign diagnosis was rendered in 12 (37%). All cases had a follow up tissue diagnosis. No false–positive cases were identified (specificity 100%). The information gained from this approach was considered helpful to the surgeons. We concluded that FNA of head and neck masses in the operating room is an accurate and sensitive diagnostic approach. The service provides helpful information to surgeons and is an additional optional diagnostic approach. Diagn. Cytopathol. 2008;36:369–374. © 2008 Wiley‐Liss, Inc.
Indications for thyroid FNA and pre‐FNA requirements: A synopsis of the National Cancer Institute Thyroid Fine‐Needle Aspiration State of the Science Conference
Authors: Cibas Edmund S. , Alexander Erik K. , Benson Carol B. , de Agustín Pedro Patricio , Doherty Gerard M. , Faquin William C. , Middleton William D. , Miller Theodore , Raab Stephen S. , White Matthew L. , Mandel Susan J. 
Published: May 2008

AbstractThe National Cancer Institute (NCI) sponsored the NCI Thyroid Fine‐Needle Aspiration (FNA) State of the Science Conference on October 22–23, 2007 in Bethesda, MD. The 2‐day meeting was accompanied by a permanent informational website and several on‐line discussions between May 1 and December 15, 2007 (http://thyroidfna.cancer.gov). This document summarizes the indications for performing an FNA of a nodule discovered by physical examination or an imaging study; the indications for using ultrasound versus palpation for guidance when performing a thyroid FNA; the issues surrounding informed consent for thyroid FNA; and the information required on a requisition form that accompanies a thyroid FNA specimen. (http://thyroidfna.cancer.gov/pages/info/agenda/) Diagn. Cytopathol. 2008;36:390–399. © 2008 Wiley‐Liss, Inc.
Training, credentialing and re‐credentialing for the performance of a thyroid FNA: A synopsis of the National Cancer Institute Thyroid Fine‐Needle Aspiration State of the Science Conference
Authors: Ljung Britt‐Marie E. , Langer Jill , Mazzaferri Ernest L. , Oertel Yolanda C. , Wells Samuel A. , Waisman Jerry 
Published: May 2008

AbstractThe National Cancer Institute (NCI) sponsored the NCI Thyroid Fine‐Needle Aspiration (FNA) State of the Science Conference on October 22–23, 2007 in Bethesda, MD. The 2‐day meeting was accompanied by a permanent informational website and several on‐line discussion periods between May 1 and December 15, 2007 (http://thyroidfna.cancer.gov). This document summarizes matters regarding training for the performance of thyroid FNA via palpation; training for the performance of thyroid FNA via ultrasound imaging, and credentialing/re‐credentialing for the performance of a thyroid FNA. (http://thyroidfna.cancer.gov/pages/info/agenda/) Diagn. Cytopathol. 2008;36:400–406. © 2008 Wiley‐Liss, Inc.
Post‐thyroid FNA testing and treatment options: A synopsis of the National Cancer Institute Thyroid Fine Needle Aspiration State of the Science Conference
Authors: Layfield Lester J. , Abrams Jacki , Cochand‐Priollet Beatrix , Evans Doug , Gharib Hossein , Greenspan Frank , Henry Michael , LiVolsi Virginia , Merino Maria , Michael Claire W. , Wang Helen , Wells Samuel A. 
Published: May 2008

AbstractThe National Cancer Institute (NCI) sponsored the NCI Thyroid Fine Needle Aspiration (FNA) State of the Science Conference on October 22–23, 2007 in Bethesda, MD. The 2‐day meeting was accompanied by a permanent informational Web site and several on‐line discussion periods between May 1 and December 15, 2007 (http://thyroidfna.cancer.gov). This document addresses follow‐up procedures and therapeutic options for suggested diagnostic categories. Follow‐up options for “nondiagnostic” and “benign” thyroid aspirates are given. The value of ultrasound examination in the follow‐up of “nondiagnostic” and “benign” thyroid aspirates is discussed. Ultrasound findings requiring reaspiration or surgical resection are described as are the timing and length of clinical and ultrasonographic surveillance for cytologically “benign” nodules. Options for surgical intervention are given for the diagnostic categories of “atypical/borderline,” “follicular neoplasm,” “suspicious for malignancy” and “malignant” (http://thyroidfna.cancer.gov/pages/info/agenda/). Diagn. Cytopathol. 2008;36:442–448. © 2008 Wiley‐Liss, Inc.
A Tetragonal Core with Asymmetric Iron Environments Supported Solely by Bis(μ‐OH){μ‐(O–H···O)} Bridging and Terminal Pyridine Amide (N, O) Coordination: A New Member of the Tetrairon(III) Family
Authors: Singh Akhilesh K. , Jacob Wilson , Boudalis Athanassios K. , Tuchagues Jean‐Pierre , Mukherjee Rabindranath 
Published: May 2008

AbstractRoom‐temperature aerobic reaction of [Fe(MeCN)4][ClO4]2 with 1,3‐bis(2‐pyridinecarboxamido)propane (H2bpp) yields the tetrairon(III) complex [Fe4(H2bpp)4(μ‐OH)2(μ‐OHO)][ClO4]7·2H2O·xMeCN (1·xMeCN, 0 ≤ x ≤ 3). Crystal structure determination reveals that 1·3MeCN is a new member of the tetrairon(III) family, bridged solely by two hydroxido ligands and a localized {O–H···O}3– bridging unit. The properties of the “tetragonal” core [Fe4(μ‐OH)2{μ‐(O–H···O)}]7+ have been investigated by variable‐temperature magnetic and Mössbauer spectroscopic measurements. Successful modeling of the data has revealed asymmetric iron environments and three types of magnetic exchange interactions [through μ‐OH and μ‐O/μ‐OH of μ‐(O–H···O) bridges]. This tetragonal core is a valuable addition to the tetrairon(III) cluster family from inorganic and bioinorganic perspectives.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
The Cyclooligomerisation of Acetylene at Metal Centres
Authors: Xu Rong , Winget Paul , Clark Timothy 
Published: May 2008

AbstractDensity‐functional theory (DFT) and QCISD(T) calculations have been used to investigate the mechanism of cyclodimerisation and cyclotrimerisation of acetylene at a cyclopentadienyl‐CoI centre. In contrast to earlier investigations, we find that the most favourable mechanism for the formation of benzene involves the insertion of an acetylene molecule into a Co–C bond of the well known cobaltacyclopentadienyl intermediate. The product of this reaction then undergoes very facile ring‐closure to benzene. This mechanism is found to be more favourable than the concerted Diels–Alder path, which is the highest in energy of the three mechanisms considered. The remaining reaction path involves initial addition of an acetylene molecule to the cyclopentadienyl ligand followed by rearrangement to give a 1,3,5‐hexatrien‐1‐ylcyclopentane ligand system, which cleaves to give benzene and cyclopentadienyl ligands. Spin crossovers between the singlet and triplet states are found for the ring‐closure of the cobaltacyclopentadienyl intermediate to give a cyclobutadiene complex and for the concerted Diels–Alder process. These spin crossovers and the reaction mechanisms in general are rationalised in terms of the concept of electron‐transfer catalysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Iridium‐Catalyzed Hydrogenation of β‐Dehydroamino Acid Derivatives Using Monodentate Phosphoramidites
Authors: Enthaler Stephan , Erre Giulia , Junge Kathrin , Schröder Kristin , Addis Daniele , Michalik Dirk , Hapke Marko , Redkin Dmitry , Beller Matthias 
Published: May 2008

AbstractThe iridium‐catalyzed asymmetric hydrogenation of 13 different β‐dehydroamino acid derivatives to give optically active β‐amino acid esters has been examined. Readily accessible monodentate octahydrobinaphthol‐based phosphoramidites were used as chiral ligands. Good to excellent enantioselectivities and yields were obtained for the E isomers, whereas poorer catalyst performance was found for the Z isomers. Importantly, to obtain high enantioselectivity, substitution at the 3,3′‐positions of the ligands was necessary. Enantioselectivities of up to 94 % ee were achieved under optimized conditions.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
The Thread & Cut Method: Syntheses of Molecular Knot Precursors
Authors: Fenlon Edward E. , Ito Brandon R. 
Published: May 2008

AbstractA novel approach to molecular knots is described. This method may allow access to smaller and more complex knots. Two knot precursors, 1a and 1b, are efficiently prepared in overall yields of 9.6 % and 8.7 %, respectively. The convergent six‐step syntheses utilize Fréchet‐type etherifications, alkyne/azide click cycloadditions, and bis‐macrolactonizations.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)