bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling of diffusion‐controlled reactions in free radical solution and bulk polymerization: Model validation by DSC experiments
Authors: Achilias Dimitris S. , Verros George D.
Published: January 2010

In this work, a detailed experimental study of diffusion‐controlled reactions in free radical polymerization by using differential scanning calorimetry (DSC) was carried out. The systems studied include the methyl methacrylate bulk polymerization as well as the solution and the bulk polymerization of vinyl acetate at a wide range of experimental conditions including initial initiator concentration, reaction temperature, and type and amount of solvent. The conversion data obtained by DSC was successfully simulated by using a mathematical model based on sound principles such as the free volume theory. The estimated parameters, by fitting predictions of this model to conversion data obtained by DSC were found to be in close agreement with the reported parameters in the literature, thus validating both the experimental and theoretical methods used in this work. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Conductivity and piezoresistivity of conductive carbon black filled polymer composite
Authors: Wang Peng , Ding Tianhuai
Published: January 2010

Dispersing conductive carbon black (CCB) particles into silicone rubber (SR), we studied the conductivity and piezoresistivity of particles filled polymer composite. The experimental results show that the conductive percolation threshold and shape exponent of composite are effected on by filler's size and reduce with filler's size decreasing. The electrical resistance and Young's model of composite have different critical filler volume fraction to fall or increase. The compressing deformation is the main reason of the piezoresistivity of composite, but the piezoresistivity is more obvious when particles have larger size or polymer matrix has smaller Young's Model. A research was done to explain the piezoresistivity through comparing CCB/SR with CCB/high density polythene (HDP). The other interesting find is that the electrical resistance of composite decreases with time under an invariant load, showing “electrical resistance creep” behavior, which is due to the composite's compressing strain creep under uniaxial pressure. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis, thermal degradation, and flame retardance of novel triazine ring‐containing macromolecules for intumescent flame retardant polypropylene
Authors: Dai Jinfeng , Li Bin
Published: January 2010

Two novel triazine ring‐containing macromolecules, designated as charring‐foaming agent 1 (CFA1) and charring‐foaming agent 2 (CFA2), were synthesized by a series of polycondensation reactions. Their chemical structures were analyzed by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (13C solid‐state NMR), and elemental analysis, and their thermal degradation properties were assessed by thermogravimetric analysis (TGA). TGA data revealed that CFA1 and CFA2 show high thermal stability and have a high propensity for char formation, their initial decomposition temperatures being 300.2°C and 287.1°C, and their char residues at 800°C amounting to 32.2 wt % and 21.1 wt %, respectively. CFA1 presents higher thermal stability and more char residue than CFA2. Based on experimental results of the flame retardancy (limiting oxygen indices values and UL‐94 V‐0 rating) and the TG data of new intumescent flame retardant polypropylene (IFR‐PP) containing CFA1 and CFA2, CFA1 exhibits more outstanding intumescent flame retardance than CFA2. IFRs containing CFA1 and CFA2 enhanced Notched Izod Impact strength of IFR‐PP, and slightly lower tensile strength of IFR‐PP. IFR2 shows more advantageous effect on mechanical properties of IFR‐PP than IFR1. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Amelioration of collagen‐induced arthritis and immune‐associated bone loss through signaling via estrogen receptor α, and not estrogen receptor β or G protein–coupled receptor 30
Authors: Engdahl Cecilia , Jochems Caroline , Windahl Sara H. , Börjesson Anna E. , Ohlsson Claes , Carlsten Hans , Lagerquist Marie K.
Published: January 2010

Objective

The effects of estrogen may be exerted via the nuclear estrogen receptors (ERs) ERα or ERβ or via the recently proposed transmembrane estrogen receptor G protein–coupled receptor 30 (GPR‐30). The purpose of this study was to elucidate the ER specificity for the ameliorating effects of estrogen on arthritis and bone loss in a model of postmenopausal rheumatoid arthritis (RA).

Methods

Female DBA/1 mice underwent ovariectomy or sham operation, and type II collagen–induced arthritis was induced. Mice were treated subcutaneously 5 days/week with the specific agonists propylpyrazoletriol (PPT; for ERα), diarylpropionitrile (DPN; for ERβ), G1 (for GPR‐30), or with a physiologic dose of estradiol. Clinical arthritis scores were determined continuously. At termination of the study, bone mineral density (BMD) was analyzed, paws were collected for histologic assessment, serum was analyzed for cytokines and markers of bone and cartilage turnover, and bone marrow was subjected to fluorescence‐activated cell sorting.

Results

Treatment with PPT as well as estradiol dramatically decreased the frequency and severity of arthritis. Furthermore, estradiol and PPT treatment resulted in preservation of bone and cartilage, as demonstrated by increased BMD and decreased serum levels of bone resorption markers and cartilage degradation markers, whereas no effect was seen after DPN or G1 treatment.

Conclusion

In a well‐established model of postmenopausal RA, ERα, but not ERβ or GPR‐30 signaling, was shown to ameliorate the disease and the associated development of osteoporosis. Since long‐term treatment with estrogen has been associated with significant side effects, increased knowledge about the mechanisms behind the beneficial effects of estrogen is useful in the search for novel treatments of postmenopausal RA.
A genome‐wide association study identifies an osteoarthritis susceptibility locus on chromosome 7q22
Authors: Kerkhof Hanneke J. M. , Lories Rik J. , Meulenbelt Ingrid , Jonsdottir Ingileif , Valdes Ana M. , Arp Pascal , Ingvarsson Thorvaldur , Jhamai Mila , Jonsson Helgi , Stolk Lisette , Thorleifsson Gudmar , Zhai Guangju , Zhang Feng , Zhu Yanyan , van der Breggen Ruud , Carr Andrew , Doherty Michael , Doherty Sally , Felson David T. , Gonzalez Antonio , Halldorsson Bjarni V. , Hart Deborah J. , Hauksson Valdimar B. , Hofman Albert , Ioannidis John P. A. , Kloppenburg Margreet , Lane Nancy E. , Loughlin John , Luyten Frank P. , Nevitt Michael C. , Parimi Neeta , Pols Huibert A. P. , Rivadeneira Fernando , Slagboom Eline P. , Styrkársdóttir Unnur , Tsezou Aspasia , van de Putte Tom , Zmuda Joseph , Spector Tim D. , Stefansson Kari , Uitterlinden André G. , van Meurs Joyce B. J.
Published: January 2010

Objective

To identify novel genes involved in osteoarthritis (OA), by means of a genome‐wide association study.

Methods

We tested 500,510 single‐nucleotide polymorphisms (SNPs) in 1,341 Dutch Caucasian OA cases and 3,496 Dutch Caucasian controls. SNPs associated with at least 2 OA phenotypes were analyzed in 14,938 OA cases and ∼39,000 controls. Meta‐analyses were performed using the program Comprehensive Meta‐analysis, with P values <1 × 10−7 considered genome‐wide significant.

Results

The C allele of rs3815148 on chromosome 7q22 (minor allele frequency 23%; intron 12 of the COG5 gene) was associated with a 1.14‐fold increased risk (95% confidence interval 1.09–1.19) of knee and/or hand OA (P = 8 × 10−8) and also with a 30% increased risk of knee OA progression (95% confidence interval 1.03–1.64) (P = 0.03). This SNP is in almost complete linkage disequilibrium with rs3757713 (68 kb upstream of GPR22), which is associated with GPR22 expression levels in lymphoblast cell lines (P = 4 × 10−12). Immunohistochemistry experiments revealed that G protein–coupled receptor protein 22 (GPR22) was absent in normal mouse articular cartilage or synovium. However, GPR22‐positive chondrocytes were found in the upper layers of the articular cartilage of mouse knee joints that were challenged with in vivo papain treatment or methylated bovine serum albumin treatment. GPR22‐positive chondrocyte‐like cells were also found in osteophytes in instability‐induced OA.

Conclusion

Our findings identify a novel common variant on chromosome 7q22 that influences susceptibility to prevalence and progression of OA. Since the GPR22 gene encodes a G protein–coupled receptor, this is potentially an interesting therapeutic target.
Mortality outcomes in pediatric rheumatology in the US
Authors: Hashkes Philip J. , Wright Bridget M. , Lauer Michael S. , Worley Sarah E. , Tang Anne S. , Roettcher Philip A. , Bowyer Suzanne L.
Published: January 2010

Objective

To describe mortality rates, causes of death, and potential mortality risk factors in pediatric rheumatic diseases in the US.

Methods

We used the Indianapolis Pediatric Rheumatology Disease Registry, which includes 49,023 patients from 62 centers who were newly diagnosed between 1992 and 2001. Identifiers were matched with the Social Security Death Index censored for March 2005. Deaths were confirmed by death certificates, referring physicians, and medical records. Causes of death were derived by chart review or from the death certificate. Standardized mortality ratios (SMRs) and 95% confidence intervals (95% CIs) were determined.

Results

After excluding patients with malignancy, 110 deaths among 48,885 patients (0.23%) were confirmed. Patients had been followed up for a mean ± SD of 7.9 ± 2.7 years. The SMR of the entire cohort was significantly decreased (0.65 [95% CI 0.53–0.78]), with differences in patients followed up for ≥9 years. The SMR was significantly greater for systemic lupus erythematosus (3.06 [95% CI 1.78–4.90]) and dermatomyositis (2.64 [95% CI 0.86–6.17]) but not for systemic juvenile rheumatoid arthritis (1.8 [95% CI 0.66–3.92]). The SMR was significantly decreased in pain syndromes (0.41 [95% CI 0.21–0.72]). Causes of death were related to the rheumatic diagnosis (including complications) in 39 patients (35%), treatment complications in 11 (10%), non‐natural causes in 25 (23%), background disease in 23 (21%), and were unknown in 12 patients (11%). Rheumatic diagnoses, age at diagnosis, sex, and early use of systemic steroids and methotrexate were significantly associated with the risk of death.

Conclusion

Our findings indicate that the overall mortality rate for pediatric rheumatic diseases was not increased. Even for the diseases and conditions associated with increased mortality, mortality rates were significantly lower than those reported in previous studies.
Genetic variants and disease‐associated factors contribute to enhanced interferon regulatory factor 5 expression in blood cells of patients with systemic lupus erythematosus
Authors: Feng Di , Stone Rivka C. , Eloranta Maija‐Leena , Sangster‐Guity Niquiche , Nordmark Gunnel , Sigurdsson Snaevar , Wang Chuan , Alm Gunnar , Syvänen Ann‐Christine , Rönnblom Lars , Barnes Betsy J.
Published: January 2010

Objective

Genetic variants of the interferon (IFN) regulatory factor 5 gene (IRF5) are associated with susceptibility to systemic lupus erythematosus (SLE). The contribution of these variants to IRF‐5 expression in primary blood cells of SLE patients has not been addressed, nor has the role of type I IFNs. The aim of this study was to determine the association between increased IRF‐5 expression and the IRF5 risk haplotype in SLE patients.

Methods

IRF‐5 transcript and protein levels in 44 Swedish patients with SLE and 16 healthy controls were measured by quantitative real‐time polymerase chain reaction, minigene assay, and flow cytometry. Single‐nucleotide polymorphisms rs2004640, rs10954213, and rs10488631 and the CGGGG insertion/deletion were genotyped in these patients. Genotypes of these polymorphisms defined both a common risk haplotype and a common protective haplotype.

Results

IRF‐5 expression and alternative splicing were significantly up‐regulated in SLE patients compared with healthy donors. Enhanced transcript and protein levels were associated with the risk haplotype of IRF5; rs10488631 displayed the only significant independent association that correlated with increased transcription from the noncoding first exon 1C. Minigene experiments demonstrated an important role for rs2004640 and the CGGGG insertion/deletion, along with type I IFNs, in regulating IRF5 expression.

Conclusion

This study provides the first formal proof that IRF‐5 expression and alternative splicing are significantly up‐regulated in primary blood cells of patients with SLE. Furthermore, the risk haplotype is associated with enhanced IRF‐5 transcript and protein expression in patients with SLE.
Proteomic analysis by two‐dimensional electrophoresis to identify the normal human chondrocyte proteome stimulated by tumor necrosis factor α and interleukin‐1β
Authors: Cillero‐Pastor Berta , Ruiz‐Romero Cristina , Caramés Beatriz , López‐Armada María J. , Blanco Francisco J.
Published: January 2010

Objective

To determine the intracellular proteome of normal human chondrocytes stimulated with interleukin‐1β (IL‐1β) and tumor necrosis factor α (TNFα) and to ascertain differences in the protein expression patterns of these 2 cytokines.

Methods

Normal human knee cartilage chondrocytes were incubated for 48 hours without stimulation or stimulated with IL‐1β (5 ng/ml) or with TNFα (10 ng/ml). For each culture condition, protein extracts from 4 normal subjects were pooled and resolved using 2‐dimensional electrophoresis. Protein spots were visualized with Sypro stain, and qualitative and quantitative analyses were performed using PDQuest software. Protein spots were then identified by mass spectrometry, using matrix‐assisted laser desorption ionization−time‐of‐flight/time‐of‐flight technology.

Results

We identified 37 spots by mass spectrometry (MS) or by MS/MS, corresponding to 35 different proteins. In IL‐1β–stimulated chondrocytes, IL‐1β was found to modulate 22 proteins, as compared with unstimulated chondrocytes. All of these proteins except connective tissue growth factor (CCND2) were up‐regulated. Proteins involved in cellular metabolism and energy (23%) that were up‐regulated or induced by IL‐1β included nicotinamide phosphoribosyltransferase, long‐chain fatty acid–coenzyme A ligase 4, δ‐aminolevulinic acid dehydratase, triosephosphate isomerase, and an isoform of glyceraldehyde‐3‐phosphate dehydrogenase. In TNFα‐stimulated chondrocytes, TNFα was found to modulate 20 proteins, as compared with unstimulated chondrocytes. All of these except chitinase 3–like 1 (cartilage glycoprotein 39), proteasome activator complex subunit 2, and G3PDH, were up‐regulated. Eighteen proteins were differently modulated by IL‐1β and TNFα. Of these, 45% were related to metabolism.

Conclusion

IL‐1β and TNFα induce different profiles of intracellular protein expression in healthy human chondrocytes. Most of the proteins that are differently regulated are proteins that are implicated in the generation of cellular energy and in glycolysis.
Synovial fibroblasts self‐direct multicellular lining architecture and synthetic function in three‐dimensional organ culture
Authors: Kiener Hans P. , Watts Gerald F. M. , Cui Yajun , Wright John , Thornhill Thomas S. , Sköld Markus , Behar Samuel M. , Niederreiter Birgit , Lu Jun , Cernadas Manuela , Coyle Anthony J. , Sims Gary P. , Smolen Josef , Warman Matthew L. , Brenner Michael B. , Lee David M.
Published: January 2010

Objective

To define the intrinsic capacity of fibroblast‐like synoviocytes (FLS) to establish a 3‐dimensional (3‐D) complex synovial lining architecture characterized by the multicellular organization of the compacted synovial lining and the elaboration of synovial fluid constituents.

Methods

FLS were cultured in spherical extracellular matrix (ECM) micromasses for 3 weeks. The FLS micromass architecture was assessed histologically and compared with that of dermal fibroblast controls. Lubricin synthesis was measured via immunodetection. Basement membrane matrix and reticular fiber stains were performed to examine ECM organization. Primary human and mouse monocytes were prepared and cocultured with FLS in micromass to investigate cocompaction in the lining architecture. Cytokine stimuli were applied to determine the capacity for inflammatory architecture rearrangement.

Results

FLS, but not dermal fibroblasts, spontaneously formed a compacted lining architecture over 3 weeks in the 3‐D ECM micromass organ cultures. These lining cells produced lubricin. FLS rearranged their surrounding ECM into a complex architecture resembling the synovial lining and supported the survival and cocompaction of monocyte/macrophages in the neo–lining structure. Furthermore, when stimulated by cytokines, FLS lining structures displayed features of the hyperplastic rheumatoid arthritis synovial lining.

Conclusion

This 3‐D micromass organ culture method demonstrates that many of the phenotypic characteristics of the normal and the hyperplastic synovial lining in vivo are intrinsic functions of FLS. Moreover, FLS promote survival and cocompaction of primary monocytes in a manner remarkably similar to that of synovial lining macrophages. These findings provide new insight into inherent functions of the FLS lineage and establish a powerful in vitro method for further investigation of this lineage.
The protective effect of antimalarial drugs on thrombovascular events in systemic lupus erythematosus
Authors: Jung Hyejung , Bobba Raja , Su Jiandong , Shariati‐Sarabi Zhaleh , Gladman Dafna D. , Urowitz Murray , Lou Wendy , Fortin Paul R.
Published: January 2010

Objective

The antimalarial medication hydroxychloroquine has been proposed as a thromboprotective agent in systemic lupus erythematosus (SLE), but studies thus far have been limited by the possibility of confounding by indication. This study was conducted to assess whether exposure to antimalarial drugs is associated with a decrease in thrombovascular events (TEs) in patients with SLE.

Methods

The study was designed as a nested case–control study embedded in an inception cohort of patients with SLE, which allowed adjustments for possible confounding by calendar year, duration of disease, duration of observation, and severity of lupus. After controlling for the possible confounding variables in conditional logistic regression models, the use of antimalarial drugs was assessed for its effects on the development of TEs in lupus patients.

Results

Fifty‐four cases of TE were identified, and these were matched with 108 control subjects (lupus patients without TEs). Univariate analyses identified older age (odds ratio [OR] 1.04, 95% confidence interval [95%CI] 1.01–1.07) or being older than age 50 years (OR 3.5, 95% CI 1.4–8.6) and ever having hypertension (OR 2.5, 95% CI 1.0–5.8) as being associated with an increased risk of TEs, whereas use of antimalarial drugs (OR 0.31, 95% CI 0.13–0.71) was associated with a decreased risk of TEs. Separate analyses were done for arterial and venous TEs, which yielded similar results. In multivariate analyses, use of antimalarial drugs (OR 0.32, 95% CI 0.14–0.74) and older age (OR 1.04, 95% CI 1.01–1.07) were the only 2 variables that remained significant.

Conclusion

The results from this nested case–control study demonstrate that, after accounting for the effects of disease severity, disease duration, and calendar year, antimalarial drugs were found to be thromboprotective, being associated with a 68% reduction in the risk of all TEs, with a range of risk reduction of at least 26% up to as high as 86%.
Gene expression profiling in autoantibody‐positive patients with arthralgia predicts development of arthritis
Authors: van Baarsen Lisa G. M. , Bos Wouter H. , Rustenburg François , van der Pouw Kraan Tineke C. T. M. , Wolbink Gerrit Jan J. , Dijkmans Ben A. C. , van Schaardenburg Dirkjan , Verweij Cornelis L.
Published: January 2010

Objective

To identify molecular features associated with the development of rheumatoid arthritis (RA), to understand the pathophysiology of preclinical development of RA, and to assign predictive biomarkers.

Methods

The study group comprised 109 anti–citrullinated protein antibody (ACPA)– and/or rheumatoid factor–positive patients with arthralgia who did not have arthritis but were at risk of RA, and 25 patients with RA. The gene expression profiles of blood samples obtained from these patients were determined by DNA microarray analysis and quantitative polymerase chain reaction.

Results

In 20 of the 109 patients with arthralgia who were at risk of RA, arthritis developed after a median of 7 months. Gene expression profiling of blood cells revealed heterogeneity among the at‐risk patients, based on differential expression of immune‐related genes. This report is the first to describe gene signatures relevant to the development of arthritis. Signatures significantly associated with arthritis development were involved in interferon (IFN)–mediated immunity, hematopoiesis, and chemokine/cytokine activity. Logistic regression analysis revealed that the odds ratio (OR) for developing arthritis within 12 months was 21.0 (95% confidence interval [95% CI] 2.8–156.1 [P = 0.003]) for the subgroup characterized by increased expression of genes involved in IFN‐mediated immunity and/or cytokine/chemokine‐activity. Genes involved in B cell immunology were associated with protection against progression to arthritis (OR 0.38, 95% CI 0.21–0.70 [P = 0.002]). These processes were reminiscent of those in patients with RA, implying that the preclinical phase of disease is associated with features of established disease.

Conclusion

The results of this study indicate that IFN‐mediated immunity, hematopoiesis, and cell trafficking specify processes relevant to the progression of arthritis independent of ACPA positivity. These findings strongly suggest that certain gene signatures have value for predicting the progression to arthritis, which will pave the way to preventive medicine.
Trefoil factor 3 is induced during degenerative and inflammatory joint disease, activates matrix metalloproteinases, and enhances apoptosis of articular cartilage chondrocytes
Authors: Rösler Sophie , Haase Tobias , Claassen Horst , Schulze Ute , Schicht Martin , Riemann Dagmar , Brandt Jörg , Wohlrab David , Müller‐Hilke Brigitte , Goldring Mary B. , Sel Saadettin , Varoga Deike , Garreis Fabian , Paulsen Friedrich P.
Published: January 2010

Objective

Trefoil factor 3 (TFF3, also known as intestinal trefoil factor) is a member of a family of protease‐resistant peptides containing a highly conserved motif with 6 cysteine residues. Recent studies have shown that TFF3 is expressed in injured cornea, where it plays a role in corneal wound healing, but not in healthy cornea. Since cartilage and cornea have similar matrix properties, we undertook the present study to investigate whether TFF3 could induce anabolic functions in diseased articular cartilage.

Methods

We used reverse transcriptase–polymerase chain reaction, Western blot analysis, and immunohistochemistry to measure the expression of TFF3 in healthy articular cartilage, osteoarthritis (OA)–affected articular cartilage, and septic arthritis–affected articular cartilage and to assess the effects of cytokines, bacterial products, and bacterial supernatants on TFF3 production. The effects of TFF3 on matrix metalloproteinase (MMP) production were measured by enzyme‐linked immunosorbent assay, and effects on chondrocyte apoptosis were studied by caspase assay and annexin V assay.

Results

Trefoil factors were not expressed in healthy human articular cartilage, but expression of TFF3 was highly up‐regulated in the cartilage of patients with OA. These findings were confirmed in animal models of OA and septic arthritis, as well as in tumor necrosis factor α– and interleukin‐1β–treated primary human articular chondrocytes, revealing induction of Tff3/TFF3 under inflammatory conditions. Application of the recombinant TFF3 protein to cultured chondrocytes resulted in increased production of cartilage‐degrading MMPs and increased chondrocyte apoptosis.

Conclusion

In this study using articular cartilage as a model, we demonstrated that TFF3 supports catabolic functions in diseased articular cartilage. These findings widen our knowledge of the functional spectrum of TFF peptides and demonstrate that TFF3 is a multifunctional trefoil factor with the ability to link inflammation with tissue remodeling processes in articular cartilage. Moreover, our data suggest that TFF3 is a factor in the pathogenesis of OA and septic arthritis.
The gross anatomy course: An analysis of its importance
Authors: Böckers Anja , Jerg‐Bretzke Lucia , Lamp Christoph , Brinkmann Anke , Traue Harald C. , Böckers Tobias M.
Published: January 2010

The gross anatomy dissection course is a cost‐intensive piece of undergraduate medical education that students and professionals alike describe as very important within the overall medical curriculum. We sought to understand more explicitly students' valuation of gross anatomy as an “important” course and so developed a quantitative longitudinal questionnaire. Medical students (n = 124) enrolled in the winter term 2006/2007 gross anatomy course at the Ulm University Faculty of Medicine were surveyed anonymously prior to, in the middle of, and at the end of the dissection course. Subgroups of students expressing rising or falling opinions of course value were identified and correlated with student opinions about the course's ability to convey professional competencies. Five‐point Likert scales were used for each survey item, which included such standardized instruments as the NeoFFI, BSI, and FBM. The study confirmed that medical students believe dissection to be valuable. Students indicated that participation in the course facilitated acquisition of anatomy knowledge as well as skills related to teamwork, coping with stress, and, to a lesser extent, time management. Students also noted that they developed less empathy than expected beforehand. Significant subgroup differences were observed relative to the competencies of teamwork, stress coping strategies, and empathy, as well as in students' stress levels associated with having to take a dissection course. Our study builds on previous work that has shown dissection courses help students develop professional competencies. The increase in professionalism might be a reason for the generally high value students place on the gross anatomy dissection course, Anat Sci Educ 3:3–11, 2010. © 2010 American Association of Anatomists.
Blue Fluorescent Amino Acids as In Vivo Building Blocks for Proteins
Authors: Merkel Lars , Hoesl Michael G. , Albrecht Marcel , Schmidt Andreas , Budisa Nediljko
Published: January 2010

In vivo expression of colored proteins without post‐translational modification or chemical functionalization is highly desired for protein studies and cell biology. Cell‐permeable tryptophan analogues, such as azatryptophans, have proved to be almost ideal isosteric substitutes for natural tryptophan in cellular proteins. Their unique spectral features, such as markedly red‐shifted fluorescence, are transmitted into protein structures upon incorporation. Among the azaindoles under study (2‐, 4‐, 5‐, 6‐, and 7‐azaindole) 4‐azaindole has exhibited the largest Stokes shift (∼130 nm) in steady‐state fluorescence measurements. It is also highly biocompatible and as 4‐azatryptophan it can be translated into target protein sequences. However, its quantum yield and fluorescence intensity are still significantly lower when compared with natural indole/tryptophan. Since azatryptophans are hydrophilic, their presence in the hydrophobic core of proteins could be harmful. In order to overcome these limitations we have performed nitrogen methylation of azaindoles and generated mono‐ and dimethylated azaindoles. Some of these methyl derivatives retain the pronounced red shift present in the parent 4‐azaindole, but with much higher fluorescence intensity (reaching the level of indole/tryptophan). Therefore, the blue fluorescence of azaindole‐containing proteins could be further enhanced by the use of methylated analogues. Further substitution of any azaindole ring with either endo‐ or exocyclic nitrogen will not yield a spectral fluorescence maximum shift beyond 450 nm under steady‐state conditions in the physiological milieu. However, green fluorescence is a special feature of tautomeric species of azaindoles in various nonaqueous solvents. Thus, the design or evolution of the protein interior combined with the incorporation of these azaindoles might lead to the generation of specific chromophore microenvironments that facilitate tautomeric or protonated/deprotoned states associated with green fluorescence.
A Computational Study of the Olefin Epoxidation Mechanism Catalyzed by Cyclopentadienyloxidomolybdenum(VI) Complexes
Authors: Comas‐Vives Aleix , Lledós Agustí , Poli Rinaldo
Published: January 2010

A DFT analysis of the epoxidation of C2H4 by H2O2 and MeOOH (as models of tert‐butylhydroperoxide, TBHP) catalyzed by [Cp*MoO2Cl] (1) in CHCl3 and by [Cp*MoO2(H2O)]+ in water is presented (Cp*=pentamethylcyclopentadienyl). The calculations were performed both in the gas phase and in solution with the use of the conductor‐like polarizable continuum model (CPCM). A low‐energy pathway has been identified, which starts with the activation of ROOH (R=H or Me) to form a hydro/alkylperoxido derivative, [Cp*MoO(OH)(OOR)Cl] or [Cp*MoO(OH)(OOR)]+ with barriers of 24.9 (26.5) and 28.7 (29.2) kcal mol−1 for H2O2 (MeOOH), respectively, in solution. The latter barrier, however, is reduced to only 1.0 (1.6) kcal mol−1 when one additional water molecule is explicitly included in the calculations. The hydro/alkylperoxido ligand in these intermediates is η2‐coordinated, with a significant interaction between the Mo center and the Oβ atom. The subsequent step is a nucleophilic attack of the ethylene molecule on the activated Oα atom, requiring 13.9 (17.8) and 16.1 (17.7) kcal mol−1 in solution, respectively. The corresponding transformation, catalyzed by the peroxido complex [Cp*MoO(O2)Cl] in CHCl3, requires higher barriers for both steps (ROOH activation: 34.3 (35.2) kcal mol−1; O atom transfer: 28.5 (30.3) kcal mol−1), which is attributed to both greater steric crowding and to the greater electron density on the metal atom.
ChemInform Abstract: Giant Magnetocaloric Effect in Tb3Rh.
Authors: Talik E. , Klimczak M.
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Hydrothermal Syntheses, Crystal Structure and Thermal Behavior of [(CH3)2NH2]2 [B5O6(OH)4]2· [HCON(CH3)2] and [NH3CH2CH2NH3]2 [B14O20(OH)6].
Authors: Li Ping , Liu Zhihong
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A New Ternary Arsenide Eu20Ni42As31: Preparation, Crystal Structure and Physical Properties.
Authors: Babizhetskyy Volodymyr , Hiebl Kurt , Simon Arndt
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Organic Solvent‐Free Direct Asymmetric Aldol Reactions Catalyzed by a Siloxy Serine Organocatalysts in Brine.
Authors: Teo Yong‐Chua , Lee Peter Peng‐Foo
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Organocatalytic Peroxy‐Asymmetric Allylic Alkylation.
Authors: Feng Xin , Yuan Yu‐Qing , Cui Hai‐Lei , Jiang Kun , Chen Ying‐Chun
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Pyranylium Salts as Synthones in the Synthesis of Substituted Benzenes.
Authors: Razus Alexandru C. , Nica Simona , Dragu Eugenia Andreea
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Efficient Routes to Pyrazolo[3,4‐b]indoles and Pyrazolo[1,5‐a]benzimidazoles via Palladium‐ and Copper‐Catalyzed Intramolecular C—C and C—N Bond Formation.
Authors: Kumar Sarvesh , Ila Hiriyakkanavar , Junjappa Hiriyakkanavar
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Allylic and Allenic Halide Synthesis via NbCl5‐ and NbBr5‐Mediated Alkoxide Rearrangements.
Authors: Ravikumar P. C. , Yao Lihua , Flemming Fraser F.
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Revisiting the Meerwein—Ponndorf—Verley Reduction: A Sustainable Protocol for Transfer Hydrogenation of Aldehydes and Ketones.
Authors: Polshettiwar Vivek , Varma Rajender S.
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis of a New Conjugated 2,2′‐(1,4‐Phenylenedivinylene)bisquinoxaline and a Series of Styryl Derivatives of Quinoxaline and Quinoline as Promising Electro‐ and Photoluminescent Materials.
Authors: Bachowska B. , Matusiak G.
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: LIC‐KOR‐Promoted Synthesis of Alkoxydienyl Amines: An Entry to 2,3,4,5‐Tetrasubstituted Pyrroles.
Authors: Blangetti Marco , Deagostino Annamaria , Prandi Cristina , Tabasso Silvia , Venturello Paolo
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Ligand‐Free Iron/Copper‐Cocatalyzed Amination of Aryl Iodides.
Authors: Wu Xiao‐Feng , Darcel Christophe
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Soluble Polymer‐Supported Organocatalysts: Asymmetric Reduction of Imines with Trichlorosilane Catalyzed by an Amino Acid Derived Formamide Anchored to a Soluble Polymer.
Authors: Malkov Andrei V. , Figlus Marek , Prestly Mark R. , Rabani Gouher , Cooke Graeme , Kocovsky Pavel
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Aryl tert‐Butyl Sulfoxide‐Promoted Highly Enantioselective Addition of Allyltrichlorosilane to Aldehydes.
Authors: Wang Peng , Chen Junmin , Cun Linfeng , Deng Jingen , Zhu Jin , Liao Jian
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: TEMPO and Carboxylic Acid Functionalized Imidazolium Salts/Sodium Nitrite: An Efficient, Reusable, Transition Metal‐Free Catalytic System for Aerobic Oxidation of Alcohols.
Authors: Miao Cheng‐Xia , He Liang‐Nian , Wang Jin‐Quan , Wang Jing‐Lun
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Stereoselective Synthesis of (Z)‐4‐(2‐Bromovinyl)benzenesulfonyl Azide (II) and Its Synthetic Utility for the Transformation to (Z)‐N‐[4‐(2‐Bromovinyl)benzenesulfonyl]imidates (V).
Authors: Zhang Wensheng , Kuang Chunxiang , Yang Qing
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: An Efficient Synthetic Method for 3,3′,4,4′‐Biphenyltetracarboxylic Anhydride.
Authors: Hu Yu Lin , Lu Ming , Liu Xiang , Wang Peng Cheng
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Isomerization of 7‐Oxabenzonorbornadienes into Naphthols Catalyzed by [RuCl2(CO)3]2.
Authors: Ballantine Melissa , Menard Michelle L. , Tam William
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: trans‐2,5‐Disubstituted Tetrahydrofurans via Addition of Carbon Nucleophiles to the Strained Bicyclic Acetal 2,7‐Dioxabicyclo[2.2.1]heptane.
Authors: Friestad Gregory K. , Lee Hye Jin
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Efficient Synthesis of Functionalized 2,3‐Di(alkenyl)benzothiophenes and Dibenzothiophenes Based on the First Heck Reactions of 2,3‐Di‐ and 2,3,6‐Tribromobenzothiophene.
Authors: Hussain Munawar , Malik Imran , Villinger Alexander , Langer Peter
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Highly Enantioselective and Organocatalytic α‐Amination of 2‐Oxindoles.
Authors: Cheng Liang , Liu Li , Wang Dong , Chen Yong‐Jun
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Benzotriazole: An Efficient Ligand for the Copper‐Catalyzed N‐Arylation of Indoles.
Authors: Verma Akhilesh Kumar , Singh Jaspal , Larock Richard C.
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Regioselective Access to Substituted Oxindoles via Rhodium‐Catalyzed Carbene C—H Insertion.
Authors: Gauthier Delphine , Dodd Robert H. , Dauban Philippe
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Oxazole Chemistry. Part 23. An Exploration of the Metal Oxide‐Assisted Decomposition and Rearrangement of N‐Acyl‐1,3‐oxazolidin‐2‐ones Leading to 2‐Aryl‐2‐oxazolines.
Authors: Deshpande Ankur A. , Gossage Robert A. , Jackson Sarah M. , Quail J. Wilson , Sadowy Amber L. , Yadav Paras N.
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Ugi Reactions with Ammonia Offer Rapid Access to a Wide Range of 5‐Aminothiazole and Oxazole Derivatives.
Authors: Thompson Mark J. , Chen Beining
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A “Click” Approach to the Synthesis of 3‐[2‐(1‐Alkyltriazol‐4‐yl)ethyl]indoles.
Authors: Petrini Marino , Shaikh Rafik R.
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis, Characterization, and Antimicrobial Activities of Clubbed [1,2,4]‐Oxadiazoles with Fluorobenzimidazoles.
Authors: Jadhav Ganesh R. , Shaikh Mohammad U. , Kale Rajesh P. , Ghawalkar Anand R. , Gill Charansingh H.
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Convenient One‐Pot Synthesis of 5‐(Substituted Amino)‐1,2,3,4‐thiatriazoles.
Authors: Katritzky Alan R. , Meher Geeta , Narindoshvili Tamari
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Asymmetric Construction of Polycyclic Indoles Through Olefin Cross‐Metathesis/Intramolecular Friedel—Crafts Alkylation under Sequential Catalysis.
Authors: Cai Quan , Zhao Zhuo‐An , You Shu‐Li
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: N,N,N′,N′‐Tetramethylchloroformamidinium Chloride Mediated Cyclizations of β‐Oxo Amides: Facile and Divergent One‐Pot Synthesis of Substituted 2H‐Pyrans, 4H‐Pyrans and Pyridin‐2(1H)‐ones.
Authors: Wang Yan , Xin Xin , Liang Yongjiu , Lin Yingjie , Duan Haifeng , Dong Dewen
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Uncatalyzed, One‐Pot Synthesis of 3,3′‐(Benzylene)bis(4‐hydroxy‐2H‐chromen‐2‐one) Derivatives under Thermal Solvent‐Free Conditions.
Authors: Shaterian Hamid Reza , Honarmand Moones
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Sc[N(SO2C8F17)2]3 Catalyzed Condensation of β‐Naphthol and Aldehydes in Fluorous Solvent: One‐Pot Synthesis of 14‐Substituted‐14H‐dibenzo[a,j]xanthenes.
Authors: Hong Mei , Cai Chun
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: CeCl3·7H2O‐Catalyzed One‐Pot Synthesis of Hantzsch 1,4‐Dihydropyridines at Room Temperature.
Authors: Sabitha Gowravaram , Arundhathi K. , Sudhakar K. , Sastry B. S. , Yadav J. S.
Published: January 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.