bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mesenchymal Stem Cells Alter Migratory Property of T and Dendritic Cells to Delay the Development of Murine Lethal Acute Graft-Versus-Host Disease
Authors: Li Hong , Guo ZiKuan , Jiang XiaoXia , Zhu Heng , Li XiuSen , Mao Ning 
Published: July 2008

AbstractDue to the potent immunoregulatory capacity, mesenchymal stem cells (MSCs) have been used in clinical trials to treat acute graft-versus-host disease (aGvHD), although the detailed in vivo mechanisms remain elusive. In a murine lethal aGvHD model, MSCs delayed the development of the disease. Interestingly, we found that MSC infusion increased the number of T lymphocytes in the secondary lymphoid organs (SLOs). Since the expression of CD62L and CCR7 is prerequisite for lymphocyte migration into SLOs, the in vitro experiments revealed that in the presence of MSCs, T lymphocytes (including CD4+CD25+ regulatory T cells) preferred to take the naive-like phenotype (CD62L+/CCR7+) in mixed lymphocyte reaction and maintained the migratory activity elicited by secondary lymphoid tissue chemokine (SLC). Dendritic cells (DCs) are the initiator of immune response. CCR7 expression is pivotal for their maturation and migration into SLOs. However, CCR7 expression and SLC-driven migratory activity of DCs were remarkably suppressed by MSC coculture. The processes above were realized mainly through secretory mechanism. Consistently, MSC infusion maintained T lymphocytes to take CD62L+/CCR7+ phenotype and decreased the CCR7 expression and proportion of DCs in SLOs of aGvHD mice. In conclusion, the altered migratory properties of T cells and DCs might contribute to the immunosuppressive activity of transplanted MSCs in the setting of aGvHD.Disclosure of potential conflicts of interest is found at the end of this article.
Stem Cell-Derived Therapeutic Myelin Repair Requires 7% Cell Replacement
Authors: Kiel Mary E. , Chen Cui P. , Sadowski Dorota , McKinnon Randall D. 
Published: July 2008

Abstract
Embryonic stem cells (ESCs) hold great potential for therapeutic regeneration and repair in many diseases. However, many challenges remain before this can be translated into effective therapy. A principal and significant limit for outcome evaluations of clinical trials is to define the minimal graft population necessary for functional repair. Here we used a preclinical model for quantitative analysis of stem cell grafts, with wild-type ESC grafted into myelin mutant shiverer hosts, to determine minimum graft levels for therapeutic benefit. Using a timed motor function test we identified three groups, including recipients indistinguishable from nongrafted shiverer controls (time [t] = 20.1 ± 1.1 seconds), mice with marginal improvement (t = 15.7 ± 1 seconds), and mice with substantial phenotype rescue (t = 5.7 ± 0.9 seconds). The motor function rescued chimeras also had a considerably extended life span (T50 &gt; 128 days) relative to both shiverer (T50 = 108 days) and the nonrescued chimeras. Retrospective genotype analysis identified a strong correlation (r2 = 0.85) between motor function and ESC-derived chimerism, with &gt; 7% chimerism required for rescue in this murine model of central nervous system myelin pathology. These results establish the minimal levels of engraftment to anticipate therapeutic repair of a cell-autonomous defect by cell transplant therapy.
Disclosure of potential conflicts of interest is found at the end of this article.
Reprogramming of Neural Progenitor Cells into Induced Pluripotent Stem Cells in the Absence of Exogenous Sox2 Expression
Authors: Eminli Sarah , Utikal Jochen , Arnold Katrin , Jaenisch Rudolf , Hochedlinger Konrad 
Published: July 2008

Abstract
Expression of the transcription factors Oct4, Sox2, Klf4, and c-Myc in mesodermal and endodermal derivatives, including fibroblasts, lymphocytes, liver, stomach, and β cells, generates induced pluripotent stem (iPS) cells. It remains unknown, however, whether cell types of the ectodermal lineage are equally amenable to reprogramming into iPS cells by the same combination of factors. To test this, we have isolated genetically marked neural progenitor cells (NPCs) from neonatal mouse brains and infected them with viral vectors expressing Oct4, Sox2, Klf4, and c-Myc. Infected NPCs gave rise to iPS cells that expressed markers of embryonic stem cells, showed demethylation of pluripotency genes, formed teratomas, and contributed to viable chimeras. In contrast to other somatic cell types, NPCs expressed high levels of endogenous Sox2 and thus did not require viral Sox2 expression for reprogramming into iPS cells. Our data show that in addition to mesoderm- and endoderm-derived cell types, neural progenitor cells of the ectodermal lineage can be reprogrammed into iPS cells, suggesting that in vitro reprogramming is a universal process. These results also imply that the combination of factors necessary for reprogramming is dependent on cellular context.
Disclosure of potential conflicts of interest is found at the end of this article.
Resistance to Antifolates in Plasmodium Falciparum, the Causative Agent of Tropical Malaria
Authors: Warhurst David C. 
Published: July 2008

Every year there are 270 million clinical attacks of malaria and 2 million deaths, caused by the protozoan Plasmodium falciparum. Most of these cases occur in Africa. Chloroquine-resistance has led to reliance on antimalarial antifolates, in particular the synergistic combination sulfadoxine/ pyrimethamine (S/P) which targets enzymatic synthesis of folate co-factors through dihydropteroate synthase (DHPS) and dihydrofolate reductase (DHFR). Resistance to S/P is now increasing and replacement antimalarials are needed. Crystal structures are not yet available for these key enzymes in the folate pathway. This review focuses on the activity of drugs on DHFR in malaria parasites, attempts to interpret differences in activity of pyrimethamine and its related drugs, and to clarify how residue changes due to point mutations determine the development of resistance. In homology-modelled P. falciparum DHFR (PfDHFR), the typical structure of four α-helices, 8-stranded β-sheet, four Loops and eight Turns is clearly seen. Long polar sequences specific for Plasmodium are inserted in Turns 1 and 2. Structures immediately concerned in drug binding are β-A, L1, α-B, α-C, T-3, β-E, α-F, and β-F. The roles of several mutations associated with resistance are discussed. In view of sequence differences in turn 3 in PfDHFR and in the human enzyme, and the marked interaction with residues of T3 of the experimental flexible antifolate WR99210 effective in pyrimethamine and cycloguanil resistance, further drug development in this area is indicated.
The structure of Iranian chemistry research, 1990–2006: An author cocitation analysis
Authors: Osareh Farideh , McCain Katherine W. 
Published: July 2008

AbstractTo study the structure of Iranian chemistry research, we identified 43 Iranian and international chemists who were highly cited in 7,682 Iranian chemistry publications (defined as an article with at least one Iranian author address) indexed in Science Citation Index (SciSearch) between 1990 and 2006, inclusive. We collected cocitation data for these authors from the entire SciSearch file (Dialog, File 34) over the time period. A principal components analysis identified seven interrelated factors accounting for 78% of the variance in the cocitation matrix. Iranian and international authors tended to load on separate factors. Three factors—synthesis of carbonyl compounds, solvent‐free synthesis of organic compounds and oxidation of organic compounds—had an inter‐correlation of | 0.3 | or higher. Physical organic chemistry and ionophores (a mixed factor of Iranian and international authors) connected at a lower value, while crown ethers and analytical chemistry were essentially uncorrelated. The PFNet structure maintained the topical factor groupings and Iranian and international authors tended to appear in separate subnetworks. Geographic and institutional influences, apparently relating in part to institutional affiliation and in part to restricted research topics, appear to underlie the primary structural features of Iranian chemistry in this time period.
High‐Density Gold Nanoparticles Supported on a [Ru(bpy)3]2+‐Doped Silica/Fe3O4 Nanocomposite: Facile Preparation, Magnetically Induced Immobilization, and Applications in ECL Detection
Authors: Guo Shaojun , Li Jing , Wang Erkang 
Published: July 2008

AbstractA large‐scale process combined sonication with self‐assembly techniques for the preparation of high‐density gold nanoparticles supported on a [Ru(bpy)3]2+‐doped silica/Fe3O4 nanocomposite (GNRSF) is provided. The obtained hybrid nanomaterials containing Fe3O4 spheres have high saturation magnetization, which leads to their effective immobilization on the surface of an ITO electrode through simple manipulation by an external magnetic field (without the need of a special immobilization apparatus). Furthermore, this hybrid nanomaterial film exhibits a good and very stable electrochemiluminescence (ECL) behavior, which gives a linear response for tripropylamine (TPA) concentrations between 5 μM and 0.21 mM, with a detection limit in the micromolar range. The sensitivity of this ECL sensor can be easily controlled by the amount of [Ru(bpy)3]2+ immobilized on the hybrid nanomaterials (that is, varying the amount of [Ru(bpy)3]2+ during GNRSF synthesis).
Reactions at the Ru–S Bonds of Coordinatively Unsaturated Ruthenium Complexes with Tethered 2,6‐Dimesitylphenyl Thiolate
Authors: Ohki Yasuhiro , Takikawa Yuko , Sadohara Hitomi , Kesenheimer Christian , Engendahl Barthel , Kapatina Elissavet , Tatsumi Kazuyuki 
Published: July 2008

AbstractCoordinatively unsaturated ruthenium complexes with a tethered SDmp (Dmp=2,6‐dimesitylphenyl) ligand, [(DmpS)Ru(PR3)][BArF4] (3 a: R=Et; 3 b: R=Ph; ArF=3,5‐(CF3)2C6H3), were synthesized by the reactions of [{(p‐cymene)RuCl}2(μ‐Cl)2], LiSDmp, phosphines, and NaBArF4. The RuS bonds in 3 a and 3 b were found to serve as the polarized reactive site in reactions with alkyl halides, diazoalkanes, (p‐tosyliminoiodo)benzene, phenylacetylene, and H2. Alkylation of 3 a and 3 b with methyl iodide or ethyl bromide occurred instantaneously to give the thioether complexes [(DmpSR′)RuX(PR3)][BArF4] (4 a: R=Et, R′=Me, X=I; 4 b: R=R′=Et, X=Br; 4 c: R=Ph, R′=Me, X=I; 4 d: R=Ph, R′=Et, X=Br). Treatment of 3 a with diazoalkanes N2CHR (R=CO2Et, SiMe3) led to the cycloaddition of carbenes to the RuS bond to form [DmpS(CHR)Ru(PEt3)][BArF4] (5 a: R=CO2Et; 5 b: R=SiMe3), whereas the reaction with (p‐tosyliminoiodo)benzene gave rise to [DmpS{NS(O)(C6H4‐4‐CH3)O}Ru(PEt3)][BArF4] (6), which contains a five‐membered ruthenacycle of RuSNSO. Addition of phenylacetylene to the RuS bond occurred reversibly to produce the vinyl sulfide complexes [DmpS(PhCCH)Ru(PR3)][BArF4] (7 a: R=Et; 7 b: R=Ph). On the other hand, the phenylacetylene at ruthenium slowly isomerized to vinylidene and bridged Ru and S in the products, [DmpS{C(CHPh)}Ru(PR3)][BArF4] (8 a: R=Et; 8 b: R=Ph). Complex 3 a catalyzed the hydrogenation of acetophenone, in which the heterolytic H–H splitting at the Ru–S site is suggested to be involved in the mechanism.
Penta(pyrenyl)[60]fullerenes: Pyrene–Pyrene and [60]Fullerene–Pyrene Interactions in the Crystal and in Solution
Authors: Matsuo Yutaka , Morita Kouhei , Nakamura Eiichi 
Published: July 2008

AbstractA new type of fullerene–pyrene hybrid molecule, C60Ar5R [Ar=1‐pyrenyl, 4‐(1‐pyrenyl)C6H4, 4‐{(1‐pyrenyl)CO2}C6H4, and 4‐{(1‐pyrenyl)(CH2)3CO2}C6H4; R=H and Me] was synthesized by a regioselective penta‐addition reaction using organocopper reagents. The compounds were investigated using electrochemical measurements, DFT calculations, single‐crystal X‐ray structural analysis, and spectroscopic and fluorescence measurements. Intramolecular and intermolecular fullerene–pyrene and pyrene–pyrene interactions were characterized in the crystals. Fluorescence measurements in dilute solutions suggested the presence of intramolecular fullerene–pyrene and pyrene–pyrene interactions.
Mitochondrial aspartate/glutamate carrier SLC25A12 gene is associated with autism
Authors: Turunen Joni A. , Rehnström Karola , Kilpinen Helena , Kuokkanen Mikko , Kempas Elli , Ylisaukko‐oja Tero 
Published: July 2008

AbstractTwo single nucleotide polymorphisms (SNP) within Mitochondrial Aspartate/Glutamate Carrier SLC25A12 gene have recently shown to be strongly associated with autism. Here, we attempted to replicate this finding in two separate Finnish samples with autism spectrum disorders. Family‐based association analysis of two SNPs, rs2056202 and rs2292813, previously shown to be associated with autism was performed in two samples with different phenotypic characteristics. The samples included 97 families with strictly defined autism and 29 extended families with Asperger syndrome (AS). We detected association at rs2292813 (FBAT, P=0.0018) in the Finnish autism sample. In, addition other family‐based analysis methods supported this finding. By contrast, analysis of the AS sample yielded no evidence for association. This study shows further support that genetic variants within SLC25A12 gene contribute to the etiology of autism.
A dynamic model for diauxic growth, overflow metabolism, and AI‐2‐mediated cell–cell communication of Salmonella Typhimurium based on systems biology concepts
Authors: Cappuyns Astrid M. , Bernaerts Kristel , Vanderleyden Jos , Van Impe Jan F. 
Published: July 2008

AbstractThe last decades, the research on bacterial cell–cell communication or quorum sensing has been quite intense. Quorum sensing allows bacteria to coordinate their behavior and to act as one entity. Quorum sensing controls microbiological functions of medical, agricultural and industrial importance and a better understanding of the underlying mechanisms and the conditions under which the signaling occurs, offers possibilities for new applications. In this article a dynamic model for diauxic growth, overflow metabolism and AI‐2‐mediated cell–cell communication of Salmonella Typhimurium is presented. The growth, and the production and uptake of the AI‐2 signaling molecule of S. Typhimurium are investigated in a controlled environment (bioreactor). In a first stage a model is developed to describe diauxic growth and overflow metabolism. This model is extended in a second stage to describe AI‐2 dynamics of S. Typhimurium in relation to the growth kinetics and biomass concentration. It is illustrated how this model can be employed to test hypotheses concerning AI‐2 dynamics on the basis of macroscopic data. Biotechnol. Bioeng. 2009;102: 280–293. © 2008 Wiley Periodicals, Inc.
PLS works
Authors: Bro R. , Eldén L. 
Published: July 2008

AbstractIn a recent paper, claims were made that most current implementations of PLS provide wrong and misleading residuals [1]. In this paper the relation between PLS and Lanczos bidiagonalization is described and it is shown that there is a good rationale behind current implementations of PLS. Most importantly, the residuals determined in current implementations of PLS are independent of the scores used for predicting the dependent variable(s). Oppositely, in the newly suggested approach, the residuals are correlated to the scores and hence may be high due to variation that is actually used for predicting. It is concluded that the current practice of calculating residuals be maintained. Copyright © 2008 John Wiley & Sons, Ltd.
Quantification of single‐stranded nucleic acid and oligonucleotide interactions with metal ions by affinity capillary electrophoresis – Part II
Authors: Stettler Alexandra R. , Chaurin Valérie , Constable Edwin C. , Housecroft Catherine E. , Schwarz Maria A. 
Published: July 2008

AbstractThe interactions between tetranucleotides or heptanucleotides and inorganic cations have been measured by affinity CZE. The variation in migration behavior with increasing concentrations of divalent cations (Ca2+, Mg2+ and Ni2+) in the running buffer was investigated and quantified by the calculation of binding constants for mononuclear and multinuclear interactions. In addition to these fundamental studies of binding equilibria, the effect of sequence and the position of the guanine transition metal‐binding site in the oligonucleotide have been investigated.
Pulsatile tinnitus: A harbinger of a greater ill?
Authors: Liess Benjamin D. , Lollar Kevin W. , Christiansen Sidney G. , Vaslow Dale 
Published: July 2008

AbstractBackground.Pulsatile tinnitus is an uncommon otologic symptom, which may be the presenting complaint of a potentially devastating pathology. Understanding this manifestation as a possible symptom of a significant vascular abnormality is crucial to guide management and treatment.Methods and Results.We describe a 38‐year‐old woman with sudden‐onset right‐sided pulsatile tinnitus. A right extracranial internal carotid artery (ICA) dissection was diagnosed with MRI/magnetic resonance angiography (MRA) and treated with anticoagulation. Follow‐up MRI/MRA demonstrated complete resolution. Two months later, left‐sided pulsatile tinnitus evolved. An MRI/MRA of the neck demonstrated left‐sided extracranial ICA dissection. She was treated in a similar fashion and a repeat MRI/MRA demonstrated its resolution.Conclusion.Spontaneous extracranial ICA dissection may present with pulsatile tinnitus as the only symptom in 4% to 50% of patients. Subsequent evolution of a contralateral dissection is even more uncommon. Generally, treatment of this phenomenon is conservative utilizing anticoagulation or aspirin; however, surgical intervention may be necessary. © 2008 Wiley Periodicals, Inc. Head Neck 2009
Association between self‐esteem and depression among patients with head and neck cancer: A pilot study
Authors: Kobayashi Mika , Sugimoto Taro , Matsuda Ayako , Matsushima Eisuke , Kishimoto Seiji 
Published: July 2008

AbstractBackground.We examined the psychological distress in patients with head and neck cancer and investigated how preoperative self‐esteem influenced psychological distress during treatment.Methods.Fifty‐eight patients who were scheduled for surgery for head and neck cancer participated. The Japanese version of hospital anxiety and depression scale (HADS) was administered preoperatively, after surgery, and 6 months postoperatively, and Rosenberg self‐esteem scale was administered preoperatively and 6 months postoperatively.Results.There were significant differences among the 3 examination periods for psychological distress; the course of anxiety and depression differed between the high self‐esteem group (HSEG) and the low self‐esteem group (LSEG). In all examination periods, anxiety and depression scores for HSEG were significantly better than for LSEG. As for depression, scores did not change significantly over time in HSEG, whereas the scores went from bad to worse in LSEG.Conclusions.Patients with cancer undergoing surgery, especially patients with low self‐esteem, need preoperative and ongoing intervention. © 2008 Wiley Periodicals, Inc. Head Neck 2008
Use of Single‐Walled Carbon Nanotubes as Reinforcing Fillers in UV‐Curable Epoxy Systems
Authors: Sangermano Marco , Borella Enrica , Priola Aldo , Messori Massimo , Taurino Rosa , Pötschke Petra 
Published: July 2008

AbstractCNT were dispersed in an epoxy matrix and cured by means of UV light. An increase on elastic modulus and Tg values was measured by DMTA analysis and attributed to the constraint effect of CNT on polymer chain mobility. Excellent scratch resistant coatings characterized by high critical load, small cracks and high recovery were obtained in the presence of a very low CNT content (0.025 wt.‐%). TEM analysis showed some isolated CNT and some cluster agglomerations of size of about 250 nm. It was shown that it was possible to decrease the surface resistivity of the cured samples by three orders of magnitude in the presence of 0.1 wt.‐% of SWCNT content.magnified image
Extended Chemical CrossLinking of a Thermoplastic Polyimide: Macroscopic and Microscopic Property Development
Authors: Aberg Christopher M. , Ozcam Ali E. , Majikes Jacob M. , Seyam Mohamed A. , Spontak Richard J. 
Published: July 2008

AbstractPolyimides are well established as gas separation membranes due to their intrinsically low free volume and correspondingly high H2 selectivity relative to other gases such as CO2. Prior studies have established that H2/CO2 selectivity can be improved by crosslinking polyimides with diamines differing in spacer length. In this work, we follow the evolution of macroscopic and microscopic properties of a commercial polyimide over long crosslinking times (tx) with 1,3‐diaminopropane. According to spectroscopic analysis, the crosslinking reaction saturates after ≈24 h, whereas tensile, nanoindentation and stress relaxation tests reveal that the material stiffens, and possesses a long relaxation time that increases with increasing tx. Although differential scanning calorimetry shows that the glass transition temperature decreases systematically with increasing tx, permeation studies indicate that the permeabilities of H2 and CO2 decrease, while the H2/CO2 selectivity increases markedly, with increasing tx. At long tx, the polyimide becomes impermeable to CO2, suggesting that it could be used as a barrier material.magnified image
High Ionic Conductivity of Transparent Film of Hydroxyapatite and Poly(vinyl alcohol) Nanocomposite
Authors: Tajitsu Yoshiro , Fukuda Kazuyuki , Takaki Tosiyuku 
Published: July 2008

AbstractSummary: Hydroxyapatite (HAp)‐polyvinyl alcohol (PVA) nanocomposite film containing Li+ was designed as a solid polymer electrolyte. A composite was prepared by reacting Ca(OH)2 with H3PO4 in the presence of PVA which is denatured in order to have the carboxyl group, and a LiN(CF3SO2)2 was added. HAp particles were commonly formed in the shape of spindles (long axis ca. 80 nm and short axis ca. 25 nm). The obtained nanocomposite film, in which HAp particles were dispersed uniformly, is transparent, flexible and drawable. Its ionic conductivity is about 10−3 S/m at room temperature. This value is very large. This high ionic conductivity is considerable on the basis of the dynamic percolation theory.
Ambipolar Blends of Cu‐Phthalocyanine and Fullerene: Charge Carrier Mobility, Electronic Structure and their Implications for Solar Cell Applications
Authors: Brütting Wolfgang , Bronner Markus , Götzenbrugger Marcel , Opitz Andreas 
Published: July 2008

AbstractSummary: Ambipolar transport has been realised in blends of the molecular hole conductor Cu‐phthalocyanine (CuPc) and the electron conducting fullerene C60. Charge carrier mobilities and the occupied electronic levels have been analyzed as a function of the mixing ratio using field‐effect transistor measurements and photoelectron spectroscopy. These results are discussed in the context of photovoltaic cells based on these materials.
New Fluorene‐Based Conjugated Copolymers Bearing Carboxylic Groups
Authors: Kukla Stanislav , Pavlačková Petra , Cimrová Věra , Výprachtický Drahomír 
Published: July 2008

AbstractSummary: New conjugated copolymers containing 9,9‐dioctylfluorene and terephthalate units (as dimethyl ester or free acid) were synthesized by the Suzuki coupling and characterized by GPC and NMR, FT‐IR and UV‐VIS spectroscopies. These copolymers proved to be good luminescent materials showing emissions in the blue region of the visible spectrum both in solution (λem = 450 nm) and in thin layers. Differences in the luminescence properties were attributed to various extents of aggregation. It was shown that interchain interaction can be avoided by the formation of the copolymer sodium salt. The copolymers were tested as active layers in light‐emitting devices and the formation of their Eu(III) complexes was studied.