bluuebunny/crossref_metadata_2025_split huggingface dataset:
Palladium‐Catalyzed Direct Arylations of Five‐Membered Heteroarenes Bearing N‐Monoalkylcarboxamide Substituents
Authors: Laidaoui Nouria , Roger Julien , Miloudi Abdellah , El Abed Douniazad , Doucet Henri 
Published: June 2011

AbstractThe palladium‐catalyzed direct arylation of furan, thiophene, pyrrole, or pyrazole derivatives bearing CONHR substituents on C2, C3, or C5 with aryl bromides was studied. The use of KOAc as the base, DMAc as the solvent, and PdCl(C3H5)(dppb) as the catalyst was found to give regioselectively and without decarbamoylation the arylated heteroaromatics. Under these conditions, the amide substituent on the heteroaromatic does not act as a directing group. A wide range of functional groups such as acetyl, formyl, ester, nitrile, trifluoromethyl, and fluoro on the aryl bromide is tolerated.
The Bacterial Lectin FimH, a Target for Drug Discovery – Carbohydrate Inhibitors of Type 1 Fimbriae‐Mediated Bacterial Adhesion
Authors: Hartmann Mirja , Lindhorst Thisbe K. 
Published: June 2011

AbstractAdhesion is a prerequisite for bacteria to colonize cell surfaces. To accomplish cellular adhesion, many bacteria use carbohydrate‐specific lectins, which are expressed as part of capillary protein appendages expanding from their surface, called fimbriae or pili. For bacteria, colonization of cell surfaces offers advantageous conditions to persist and multiply. For the host, however, bacterial colonization can be affiliated with severe health problems such as inflammation. Therefore, to combat bacterial adhesion and inflammatory diseases, investigation of the molecular and biophysical details of the relevant lectin–carbohydrate interactions is important. Understanding molecular carbohydrate recognition can lead to the development of high‐affinity inhibitors of bacterial lectins. That way, interfering with the bacterial attachment to surfaces proves the vision of an antiadhesion therapy, among others, against uropathogenic E. coli (UPEC). One of the most important and best investigated bacterial lectins is the mannose‐specific protein FimH, which is expressed on the tips of type 1 fimbriae. During the last 30 years, many natural as well as synthetic mannosidic ligands of FimH have been designed and tested for their inhibitory potencies. We report key results and comment on key problems and perspectives of this research.
Dual Secondary Amine/N‐Heterocyclic Carbene Catalysis in the Asymmetric Michael/Cross‐Benzoin Cascade Reaction of β‐Oxo Sulfones with Enals
Authors: Enders Dieter , Grossmann André , Huang He , Raabe Gerhard 
Published: June 2011

AbstractPolyfuncionalized cyclopentanones with three contiguous stereogenic centers were formed in good to excellent yields and stereoselectivities by utilizing a secondary amine/N‐heterocyclic carbene catalytic system in the reaction of β‐oxo sulfones with unsaturated aldehydes. In addition, the influence of the catalysts on the diastereoselectivity of the final product was studied by 1H NMR spectroscopy.
Are sexualized women complete human beings? Why men and women dehumanize sexually objectified women
Authors: Vaes Jeroen , Paladino Paola , Puvia Elisa 
Published: June 2011

AbstractFocusing on the dehumanization of sexually objectified targets, study 1 tested the extent to which objectified and non‐objectified male and female publicity photos were associated with human compared to animal concepts. Results confirmed the hypothesis that, among all targets, only objectified women were associated with less human concepts. This pattern of results emerged for both male and female participants but likely for different reasons. Study 2 directly looked at female and male participants' affinity with sexually objectified women. Results indicated that the more women distanced themselves from sexually objectified women the more they dehumanized them, whereas men's sexual attraction moderated their tendency to dehumanize female targets. In study 3, this latter motivation was operationalized as the activation of a sex goal and showed to trigger man's but not woman's dehumanization of female targets. Overall, the present set of studies show that only sexually objectified women are dehumanized by both men and women but for different reasons. Whereas sexual attraction shifts a men's focus of a female target away from her personality onto her body triggering a dehumanization process, women are more inclined to dehumanize their sexually objectified counterparts the more they distance themselves from these sexualized representations of their gender category. Copyright © 2011 John Wiley & Sons, Ltd.
Highly Efficient and Stable Palladium Nanoparticles Supported on an Ionic Liquid Silica SolGel Modified Electrode
Authors: Safavi A. , Banazadeh A. R. 
Published: June 2011

AbstractA carbon ionic liquid electrode modified with a thin layer of silica solgel containing phosphinite ionic liquid was prepared for deposition of palladium nanoparticles. Palladium nanoparticles were formed easily by simple contact of the modified electrode with palladium chloride solution. The novel material overcomes the shortcomings of conventionally modified electrodes with a thin layer of silica solgel, due to the existence of ionic liquid in silica matrix. A crack‐free solgel matrix was obtained and also, the uniform porous structure of the ionic liquid‐solgel matrix resulted in a fast mass transport and increased ionic conductivity. The electrode exhibits high electrocatalytic effects towards hydrazine and ascorbic acid. It is very stable against repetitive cycling in the applied potential window.
Tract‐based magnetic resonance spectroscopy of the cingulum bundles at 7 T
Authors: Mandl René C.W. , van den Heuvel Martijn P. , Klomp Dennis W.J. , Boer Vincent O. , Siero Jeroen C.W. , Luijten Peter R. , Hulshoff Pol Hilleke E. 
Published: June 2011

AbstractThe cingulum bundle is a white matter fiber bundle in the human brain that is believed to be implicated in various neurological and psychiatric diseases. Subtle disease‐related differences in metabolite concentrations in the cingulum tracts that may underlie these diseases may be detected using MR spectroscopic information. However, to date, limited signal to noise and lack of spatial resolution have prevented a reliable and reproducible measurement of metabolites in the cingulum bundle in vivo. Here we propose a new method that combines MR spectroscopic imaging at 7 T with fiber tracking to select only those MR spectroscopy voxels that are actually part of the cingulum bundles. The spectra of the selected spectroscopy voxels are processed per voxel and then combined yielding one spectrum at high spectral resolution for each cingulum bundle. In this way sensitivity is increased, as large parts of the cingulum are included while partial volume effects with both gray matter and white matter from other tracts is kept to a minimum. Three healthy volunteers were scanned to assess the feasibility of the method. For all three healthy volunteers spectra for the left and right cingulum tracts were computed, partial volume fractions calculated and metabolite fractions were quantified yielding similar results suggesting that tract‐based MR spectroscopy allows us to study metabolic concentrations of individual white matter fiber bundles with high sensitivity and high specificity. Hum Brain Mapp, 2011. © 2011 Wiley‐Liss, Inc.
Constituents of the Endophytic Fungus Annulohypoxylon boveri var. microspora BCRC 34012
Authors: Cheng Ming‐Jen , Wu Ming‐Der , Hsieh Sung‐Yuan , Hsieh Ming‐Tsuen , Chen Ih‐Sheng , Yuan Gwo‐Fang 
Published: June 2011

AbstractA new azaphilone metabolite with a new substitution pattern, named annulohypoxylin (1), together with twelve known compounds, were isolated from the BuOH‐soluble fraction of the 95% EtOH extract of long‐grain rice (Oryza sativa) fermented with the endophytic fungus Annulohypoxylon boveri var. microspora (BCRC 34012). Annulohypoxylin (1) contains a dihydrobenzofuran‐2,4‐dione backbone, 1‐hydroxyoctyl side chain, and one γ‐lactone ring. Its structure was determined on the basis of extensive 1D‐ and 2D‐NMR analyses in combination with HR‐ESI‐MS. The relative configuration of 1 was confirmed by NOESY experiment. Other known compounds were identified by comparing their spectral data with those in the literature. All known compounds were isolated from this species for the first time.
Citropremide and Citropridone: A New Ceramide and a New Acridone Alkaloid from the Stem Bark of Citropsis gabunensis
Authors: Tsassi Béatrice Valerie , Hussain Hidayat , Geagni Albertine , Dongo Etienne , Ahmed Ishtiaq , Riaz Muhammad , Krohn Karsten 
Published: June 2011

AbstractThe structure elucidation and complete 1H‐ and 13C‐NMR assignments are reported for two new compounds: the ceramide citropremide (1), and the acridone alkaloid citropridone (2). Both of these secondary metabolites were isolated from the stem bark of Citropsis gabunensis. High‐resolution mass, IR and UV spectrometry, and NMR experiments including COSY, HMQC, and HMBC were used for the determination of the structures and NMR spectral assignments.
Copper‐Catalyzed Bis(methoxycarbonyl)carbene Reactions of α,β‐Unsaturated Carboxamides
Authors: Merey Gökçe , Anaç Olcay 
Published: June 2011

AbstractThe [Cu(acac)2]‐catalyzed reactions of α,β‐unsaturated carboxamides with dimethyl diazomalonate yielded dihydrofuran derivatives by a 1,5‐electrocyclic reaction at C(β), and butadiene derivatives by carbene addition reaction at C(α) (Schemes 4 and 5; Table). Phenyl substituents at the N‐atom of the amides seem to be effective on the reaction pathways (Table).
Isolation and Structural Elucidation of Novel Mycosporine‐Like Amino Acids as Alarm Cues in the Defensive Ink Secretion of the Sea Hare Aplysia californica
Authors: Kamio Michiya , Kicklighter Cynthia E. , Nguyen Linh , Germann Markus W. , Derby Charles D. 
Published: June 2011

AbstractThree new mycosporine‐like amino acids (MAAs), aplysiapalythines A, B, and C (1, 2, and 3, resp.) were isolated from opaline, a glandular component of the defensive ink secretion of sea hares (Aplysia californica) collected from waters off southern California. Here, we report the structure of these MAAs determined by mass spectrometry and NMR data. These new MAAs are structurally related to two known MAAs that are also present in sea hare opaline, i.e., asterina 330 (4) and palythine (5), and for which we also provide detailed data here for comparison. The fact that three of the five MAAs that we identified from sea hare opaline are novel molecules is interesting given that this represents a relatively large addition to the current list of known MAAs. This is likely because most researchers have identified MAAs through HPLC with UV detection, which is imprecise given similarities in UV spectra for different MAAs. Our findings suggest that there is much greater diversity of MAAs than is currently known. Results published elsewhere show that 1, 2, and 4 are alarm cues for conspecific sea hares at natural concentrations, but 3 and 5 are not.
Cigarette smoking and risk of histological subtypes of epithelial ovarian cancer in the EPIC cohort study
Authors: Gram Inger T. , Lukanova Annekatrin , Brill Ilene , Braaten Tonje , Lund Eiliv , Lundin Eva , Overvad Kim , Tjønneland Anne , Clavel‐Chapelon Francoise , Chabbert‐Buffet Nathalie , Bamia Christina , Trichopoulou Antonia , Zylis Dimosthenis , Masala Giovanna , Berrino Franco , Galasso Rocco , Tumino Rosario , Sacerdote Carlotta , Gavrilyuk Oxana , Kristiansen Steinar , Rodríguez Laudina , Bonet Catalina , Huerta José María , Barricarte Aurelio , Sánchez Maria‐José , Dorronsoro Miren , Jirström Karin , Almquist Martin , Idahl Annika , Bueno‐de‐Mesquita H. Bas , Braem Marie , Onland‐Moret Charlotte , Tsilidis Konstantinos K. , Allen Naomi E. , Fedirko Veronika , Riboli E. , Kaaks Rudolf 
Published: June 2011

AbstractNew data regarding a positive association between smoking and risk of epithelial ovarian cancer (EOC), especially the mucinous tumor type, has started to emerge. The purpose of this study was to examine the association between different measures of smoking exposures and subtypes of EOC in a large cohort of women from 10 European countries. The European Prospective Investigation into Cancer and Nutrition (EPIC) cohort is a multicenter prospective study initiated in 1992. The questionnaires included data about dietary, lifestyle, and health factors. Information about cigarette smoking was collected from individuals in all participating countries. We used Cox proportional hazard regression models to estimate hazard ratio (HR) of EOC overall and serous, mucinous, and endometroid histological subtypes, with 95% confidence intervals (CIs) associated with different measures of smoking exposures adjusting for confounding variables. Altogether 836 incident EOC cases were identified among 326,831 women. The tumors were classified as 400 serous, 83 mucinous, 80 endometroid, 35 clear cell, and 238 unspecified. Compared with never smokers, current smokers had a significantly increased risk for mucinous tumors [HR = 1.85 (95% CI 1.08–3.16)] and those smoking more than 10 cigarettes per day had a doubling in risk [HR = 2.25(95% CI 1.26–4.03)] as did those who had smoked less than 15 pack‐years of cigarettes [HR = 2.18 (95% CI 1.07–4.43)]. The results from the EPIC study add further evidence that smoking increases risk of mucinous ovarian cancer and support the notion that the effect of smoking varies according to histological subtype.
New role of the human equilibrative nucleoside transporter 1 (hENT1) in Epithelial‐to‐mesenchymal transition in renal tubular cells
Authors: Guillén‐Gómez Elena , Pinilla‐Macua Itziar , Pérez‐Torras Sandra , Choi Doo‐Sup , Arce Yolanda , Ballarín José A. , Pastor‐Anglada Marçal , Díaz‐Encarnación Montserrat M. 
Published: June 2011

AbstractEpithelial‐to‐mesenchymal transition (EMT) is an important pro‐fibrotic event in which tubular epithelial cells are transformed into myofibroblasts. Nucleoside transporters (NT) are regulated by many factors and processes, some of which are involved in fibrosis, such as cytokines, inflammation, and proliferation. Equilibrative nucleoside transporter 1 (ENT1) has been proved to be the most widely expressed adenosine transporter. In that sense, ENT1 may be a key player in cell damage signaling. Here we analyze the role of human ENT1 (hENT1) in the EMT process in proximal tubular cells. Addition of the main inducer of EMT, the transforming growth factor‐β1, to HK‐2 cells increased hENT1 mRNA and protein level expression. ENT1‐mediated adenosine uptake was also enhanced. When cells were incubated with dipyridamole to evaluate the potential contribution of ENT1 to EMT by blocking its transport activity, EMT was induced. Moreover, the knock down of hENT1 with siRNA induced EMT and collagen production in HK‐2 cells. Kidneys isolated from ENT1 knockout mice showed higher levels of interstitial collagen and α‐SMA positive cells than wild‐type mice. Our results point to a new potential role of hENT1 as a modulator of EMT in proximal tubular cells. In this sense, hENT1 could be involved in renal protection processes, and the loss or reduced expression of hENT1 would lead to an increased vulnerability of cells to the onset and/or progression of renal fibrosis. J. Cell. Physiol. 227: 1521–1528, 2012. © 2011 Wiley Periodicals, Inc.
Two mutations impair the stability and function of ubiquitin‐activating enzyme (E1)
Authors: Lao Taotao , Chen Shuyang , Sang Nianli 
Published: June 2011

AbstractProtein ubiquitination plays critical roles in the regulation of multiple cellular processes including cell proliferation, signal transduction, oncogenesis, and hypoxic response. TS20 is a Balb3T3‐derived cell line in which ubiquitination is inhibited by restrictive temperature. While TS20 has been used to elucidate the degradation of many important proteins including p53, p27, HIF‐1α, and ornithine decarboxylase, the molecular basis of its temperature sensitivity has not been fully determined. We cloned full‐length E1 cDNA from TS20. Sequencing analysis revealed two point mutations (nt736G to A and nt2313G to C) that lead to substitution of aa189A to T and aa714W to C, respectively. Transient transfection assays revealed that mutant E1 was less stable than its wild‐type counterpart, and restrictive temperature (39°C) accelerated its degradation. Under permissive temperature, reverting aa714C to W significantly improved E1 stability and activity. Under restrictive temperature, reverting of both substitutions was required to fully restore E1 stability. Similar results were observed when the mutants were expressed in non‐TS20 cells, indicating the mutations are sufficient for its temperature sensitive degradation observed in TS20 cells. Functionally, reverting aa714C to W was sufficient to facilitate the monoubiquitination of H2A and to support TS20 growth at 39°C. It also significantly improved the ubiquitination‐dependent disposal of HIF‐1α. Our data conclusively demonstrate that mutations introgenic to UVBE1 cause E1 instability, which leads to deficiency of E1 function. Our data establish the molecular basis for unambiguous interpretation of experimental data based on TS20 cells, and provide new insight into the structural determinants of E1 stability. J. Cell. Physiol. 227: 1561–1568, 2012. © 2011 Wiley Periodicals, Inc.
Lithium regulates keratinocyte proliferation via glycogen synthase kinase 3 and NFAT2 (nuclear factor of activated T cells 2)
Authors: Hampton Philip J. , Jans Ralph , Flockhart Ross J. , Parker Graeme , Reynolds Nick J. 
Published: June 2011

AbstractCertain environmental factors including drugs exacerbate or precipitate psoriasis. Lithium is the commonest cause of drug‐induced psoriasis but underlying mechanisms are currently unknown. Lithium inhibits glycogen synthase kinase 3 (GSK‐3). As lithium does not exacerbate other T‐cell‐mediated chronic inflammatory diseases, we investigated whether lithium may be acting directly on epidermal keratinocytes by inhibiting GSK‐3. We report that lithium‐induced keratinocyte proliferation at therapeutically relevant doses (1–2 mM) and increased the proportion of cells in S phase of the cell cycle. Inhibition of GSK‐3 in keratinocytes by retroviral transduction of GSK‐binding protein (an endogenous inhibitory protein) or through a highly selective pharmacological inhibitor also resulted in increased keratinocyte proliferation. Nuclear factor of activated T cells (NFAT) is an important substrate for GSK‐3 and for cyclosporin, an effective treatment for psoriasis that inhibits NFAT activation in keratinocytes as well as in lymphocytes. Both lithium and genetic/pharmacological inhibition of GSK‐3 resulted in increased nuclear localization of NFAT2 (NFATc1) and increased NFAT transcriptional activation. Finally, retroviral transduction of NFAT2 increased keratinocyte proliferation whereas siRNA‐mediated knockdown of NFAT2 reduced keratinocyte proliferation and decreased epidermal thickness in an organotypic skin equivalent model. Taken together, these data identify GSK‐3 and NFAT2 as key regulators of keratinocyte proliferation and as potential molecular targets relevant to lithium‐provoked psoriasis. J. Cell. Physiol. 227: 1529–1537, 2012. © 2011 Wiley Periodicals, Inc.
Strong expression association between matriptase and its substrate prostasin in breast cancer
Authors: Bergum Christopher , Zoratti Gina , Boerner Julie , List Karin 
Published: June 2011

AbstractBreast cancer tumorigenesis is accompanied by increased levels of extracellular proteases that are capable of remodeling the extracellular matrix as well as cleaving and activating growth factors and signaling receptors that are critically involved in neoplastic progression. Multiple studies implicate the membrane anchored serine protease matriptase (also known as MT‐SP1 and epithin) in breast cancer. The pro‐form of the GPI‐anchored serine protease prostasin has recently been identified as a physiological substrate of matriptase and the two proteases are co‐expressed in multiple healthy tissues. In this study, the inter‐relationship between the two membrane‐anchored serine proteases in breast cancer was investigated using breast cancer cell lines and breast cancer patient samples to delineate the association between matriptase and prostasin. We used Western blotting to determine the expression of matriptase and prostasin proteins in a panel of breast cancer cell lines and immunohistochemistry to assess the expression in serial sections from breast cancer tissue arrays. We demonstrate that the expression of matriptase and prostasin is closely correlated in breast cancer cell lines as well as in breast cancer tissue samples. Furthermore, matriptase and prostasin display a near identical spatial expression pattern in the epithelial compartment of breast cancer tissue. These data suggest that the matriptase–prostasin cascade might play a critical role in breast cancer. J. Cell. Physiol. 227: 1604–1609, 2012. © 2011 Wiley Periodicals, Inc.
Runx1 and C/EBPβ transcription factors directly up‐regulate P2X3 gene transcription
Authors: Ugarte Giorgia D. , Opazo Tatiana , Leisewitz Francisco , van Zundert Brigitte , Montecino Martin 
Published: June 2011

AbstractRecent evidence indicates that transcription factor Runx1 modulates the expression of several phenotypic markers in dorsal root ganglia (DRGs) neurons, including the pain‐related P2X3 receptor. In several cell lineages C/EBP transcription factors interact with the Runx factor family members to jointly bind and activate transcription of target genes. Here, we examine whether these two transcription factors directly regulate P2X3 gene expression. Through in silico analyses of the first 2 kb of the P2X3 gene promoter we identified putative consensus‐binding sites for both Runx1 and C/EBPβ transcription factors. Transient over‐expression in PC12 cells of either Runx1 or C/EBPβ increases P2X3 gene promoter activity and co‐expression of both factors results in an additive stimulatory effect on the promoter function. Accordingly, chromatin immunoprecipitation assays demonstrate that both Runx1 and C/EBPβ bind to the P2X3 promoter in PC12 cells expressing this gene. Site‐directed mutagenesis of the proximal Runx1 and C/EBPβ consensus elements in the P2X3 promoter decrease Runx1‐ and C/EBPβ‐mediated transcriptional activity. Moreover, C/EBPβ‐mediated enhancement of the P2X3 promoter requires a functional Runx1 binding site. Altogether our results support a functional and coordinated role for Runx1 and C/EBPβ transcription factors during activation of P2X3 gene transcription. J. Cell. Physiol. 227: 1645–1652, 2012. © 2011 Wiley Periodicals, Inc.
Embryologic origin of endometriosis: Analysis of 101 human female fetuses
Authors: Signorile Pietro G. , Baldi Feliciano , Bussani Rossana , Viceconte Rosa , Bulzomi Pamela , D'Armiento Mariarosaria , D'Avino Alfredo , Baldi Alfonso 
Published: June 2011

AbstractThe etiology of endometriosis, a gynecological disease characterized by the presence of endometrial glands and stroma outside the uterine cavity, is still unknown. Our research group has recently demonstrated the presence of ectopic endometrium in human female fetuses at different gestational ages. In this manuscript we describe four new cases of fetal endometriosis found among a series of 52 female fetuses analyzed at autopsy. The anatomical localization of this ectopic endometrium, and its histological and immunohistochemical characteristics are depicted. We suggest that endometriosis is caused by dislocation of primitive endometrial tissue outside the uterine cavity during organogenesis. The clinical and pathological implications of these findings are discussed. J. Cell. Physiol. 227: 1653–1656, 2012. © 2011 Wiley Periodicals, Inc.