bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biomimetic Hydroxylation Catalysis Through Self‐Assembly of a Bis(pyrazolyl)methane Copper–Peroxo Complex
Authors: Wilfer Claudia , Liebhäuser Patricia , Erdmann Hannes , Hoffmann Alexander , Herres‐Pawlis Sonja 
Published: December 2014

AbstractWe synthesised and characterised four copper complexes (with copper in the oxidation states I and II) with the bis(pyrazolyl)methane ligands HC(3‐tBuPz)2(Py) and HC(3‐tBuPz)2(Qu). With the quinolinyl ligand (2‐quinolinyl)bis(3‐tert‐butylpyrazolyl)methane [HC(3‐tBuPz)2(Qu)] we obtained the tetrahedral monofacial complex [CuCl{HC(3‐tBuPz)2(Qu)}] (C1) and with the pyridinyl ligand (2‐pyridinyl)bis(3‐tert‐butylpyrazolyl)methane [HC(3‐tBuPz)2(Py)] we obtained the three complexes [CuCl{HC(3‐tBuPz)2(Py)}] (C2), [CuBr2{HC(3‐tBuPz)2(Py)}] (C3) and [CuCl2{HC(3‐tBuPz)2(Py)}] (C4), which are also monofacially coordinated. The molecular structures were analysed and compared with density functional theory calculations, which included natural bond orbital (NBO) analysis. C1 can, when generated in situ, serve as part of a precursor, used for the activation of oxygen as tyrosinase model. We observe the self‐assembly of a peroxo–dicopper complex P with the HC(3‐tBuPz)2(Qu) ligand, which is able to perform catalytic hydroxylation catalysis with phenols. DFT calculations were also carried out to understand the electronic transitions responsible for the UV/Vis bands in the corresponding spectra of the peroxo species.
Sn6[P12N24] – A Sodalite‐Type Nitridophosphate
Authors: Pucher Florian J. , Frhr. von Schirnding Constantin , Hummel Franziska , Celinski Vinicius R. , Schmedt auf der Günne Jörn , Gerke Birgit , Pöttgen Rainer , Schnick Wolfgang 
Published: December 2014

AbstractSn6[P12N24] was synthesized from Sn and HPN2 at 820 °C in an evacuated silica glass ampoule. According to powder X‐ray diffraction investigations and Rietveld refinement [space group I$\bar {4}$3m (no. 217), a = 8.2882(2) Å, RP = 0.03645, wRP = 0.04613], Sn6[P12N24] crystallizes with a sodalite‐type structure with a reduced occupation factor of 3/4 for the Sn atom at Wyckoff site 8c and an empty Wyckoff site 2a at the center of the β‐cages. The structural results are further corroborated by energy‐dispersive X‐ray spectroscopy (EDX) analyses, solid‐state NMR spectroscopy, and theoretical investigations (DFT), including density of states (DOS), energy/volume, and electron localization (ELF) calculations. The 119Sn Mössbauer spectrum shows a single, quadrupole‐split signal for SnII at an isomer shift of 3.05 mm/s. In addition to SiPN3 with a defective wurtzite type of structure, the nitridophosphate sodalite Sn6[P12N24] represents the second ternary nitridophosphate containing only p‐block elements.
Modified Julia Olefination on Sugar‐Derived Lactones: Synthesis of Difluoro‐exo‐glycals
Authors: Habib Samuel , Gueyrard David 
Published: December 2014

AbstractWe report the preparation of difluoro‐exo‐glycals by gem‐difluoroolefination of benzylated sugar‐derived lactones using a modified Julia reaction. The addition is highly stereoselective, and the Smiles‐rearrangement–elimination sequence can be carried out under microwave irradiation.
Cycloaddition of Arynes and Cyclic Enol Ethers as a Platform for Access to Stereochemically Defined 1,2‐Disubstituted Benzocyclobutenes
Authors: Yedulla Vijayendar R. , Pradhan Padmanava , Yang Lijia , Lakshman Mahesh K. 
Published: December 2014

AbstractBenzocyclobutenes (BCBs) are important entities in a multitude of areas, such as complex organic synthesis, materials and polymer chemistry, and electronics. Whereas reactions between arynes and ketene acetals have been well studied, reactions with cyclic enol ethers are unknown. A cis olefin geometry in cyclic enol ethers makes them well suited for formal [2+2] cycloaddition with arynes than for competing ene reactions, making them effective reactants. Reactions of 2,3‐dihydrofuran, 2,3‐dihydro‐3H‐pyran, 5‐butyl‐2,3‐dihydrofuran, (S)‐2‐[(benzyloxy)methyl]‐2,3‐dihydrofuran, and 1,4‐dioxene with various arynes were successful. An advantage of the use of cyclic enol ethers is that despite the plausible intermediacy of zwitterionic intermediates, the products are limited to a cis ring junction. This can be exploited for potential access to stereochemically defined 1,2‐disubstituted BCBs. As a demonstration, ether ring cleavage with BBr3 provided trans‐functionalized BCBs, and displacement with azide then provided cis derivatives. DFT computations have been utilized to understand the structures of three arynes in relation to the cycloadditions and for a predictive evaluation of product ratios in two cases. A comparative evaluation of the HOMO energies of a related series of cyclic olefins has also been performed by DFT computations.
Complementary Synthetic Approaches to Elongated Polycyclic Arenes with Regioisomeric Carboxylic Substitution Patterns
Authors: Bock Harald , Carré Pauline , Hillard Elizabeth A. , Durola Fabien 
Published: December 2014

AbstractThe reaction of 1,5‐dibromoanthracene with butyllithium and diethyloxalate followed by saponification gives anthrylene‐1,5‐diglyoxylic acid as a bifunctional reactant. Its double condensation with 2‐bromophenylacetic acid, followed by double cyclization, leads to a bright‐orange near‐linear dinaphtho‐anthracene‐tetracarboxdiimide with substituents on the naphthalene moieties. An analogous condensation‐cyclization sequence of 2,5‐dibromophenylene‐1,4‐diacetic acid with 1‐naphthylglyoxylic acid leads to an isomeric red diimide substituted on the anthracene nucleus. The striking difference in band gaps shows that diimide substitution on the central moiety of diareno[a,h]anthracenes is particularly efficient in inducing long‐wavelength absorption. The substitution dependence of the band gap is found to be mainly caused by a variation of the reduction potentials with substituent position, whereas the oxidation potentials are largely substitution‐independent.
A Route for the Total Synthesis of Enantiomerically Enriched Jasmonates 12‐COOH‐JA and 12‐COOH‐JA‐Ile
Authors: Heinrich Clément F. , Widemann Emilie , Sanz Jérémie , Lugan Raphaël , Heitz Thierry , Pinot Franck , Miesch Michel , Miesch Laurence 
Published: December 2014

AbstractEnantiomerically enriched oxidized conjugated or non‐conjugated jasmonate derivatives were obtained through 3‐alkynoates. Stereoselective reduction of the triple bond afforded exclusively the Z isomer. Protection of the amide function led to the non‐conjugated derivatives, whereas the free amides provided the oxidized isoleucine derivatives of jasmonate.
Tuning the Isomeric Fused Heteroaromatic Core of Small Donor–Acceptor Molecules to Alter Their Crystalline Nature and Enhance Photovoltaic Performance
Authors: Dang Dongfeng , Xiao Manjun , Zhou Pei , Zhong Juan , Fan Jiang , Su Ning , Xiong Wenjing , Yang Chuncheng , Wang Qiong , Wang Yafei , Pei Yong , Yang Renqiang , Zhu Weiguo 
Published: December 2014

AbstractNovel donor–acceptor‐type molecules, endo‐DBST(BT‐Cz)2 and exo‐DBST(BT‐Cz)2, were designed with benzothiadiazole‐carbazole (BT‐Cz) based arms and isomeric cores of dibenzosexithiophene (DBST), in which sulfur atoms at two lateral thienos in DBST are face‐to‐face for the endo‐derivative and back‐to‐back for exo‐derivative. In contrast to the endo‐type, the exo‐form exhibited highly crystalline properties, leading to an increased hole mobility up to 1.1 × 10–4 cm V–1s–1. A significant effect of the isomeric DBST cores on the photovoltaic properties was also observed in the organic photovoltaic (OPV) cells. The maximum power conversion efficiency of 2.13 % with a fill factor up to 61.41 % was obtained for the exo‐DBST(BT‐Cz)2‐based devices, which are 1.2 times higher than that in the endo‐DBST(BT‐Cz)2‐based cells. Our results demonstrate that tuning the isomeric core would increase the carrier mobility significantly and consequently enhance the photovoltaic performance of the resulting molecules in OPV cells.
Trends in chemoradiation use in elderly patients with head and neck cancer: Changing treatment patterns with cetuximab
Authors: Baxi Shrujal S. , O'Neill Caitriona , Sherman Eric J. , Atoria Coral L. , Lee Nancy Y. , Pfister David G. , Elkin Elena B. 
Published: December 2014

AbstractBackgroundCetuximab was approved for use in chemoradiation therapy (CRT) for locally advanced head and neck squamous cell carcinoma (HNSCC) in 2006.MethodsAmong 3705 patients with locally advanced HNSCC identified in the linked Surveillance Epidemiology and End Results (SEER) Medicare database, we assessed treatment trends, including surgery, radiation therapy (RT), CRT, and specific agents used in CRT. We examined the influence of demographic and clinical characteristics on the likelihood of receiving CRT before and after 2006.ResultsChemoradiation use increased from 29% of patients diagnosed in 2001 to 61% in 2009 (p < .0001). Compared to before 2006, neither age nor comorbidity score was associated with receipt of CRT after 2006. Platinum combinations were the most commonly used concurrent chemotherapies before 2006, but, since then, cetuximab has become the most commonly used agent.ConclusionThe use of CRT has increased substantially and cetuximab may have increased CRT use, especially in older and sicker patients. © 2015 Wiley Periodicals, Inc. Head Neck 38: E165–E171, 2016
All‐cause mortality increased by environmental cadmium exposure in the Japanese general population in cadmium non‐polluted areas
Authors: Suwazono Yasushi , Nogawa Kazuhiro , Morikawa Yuko , Nishijo Muneko , Kobayashi Etsuko , Kido Teruhiko , Nakagawa Hideaki , Nogawa Koji 
Published: December 2014

AbstractThe aim of the present study was to evaluate the effect of environmental cadmium (Cd) exposure indicated by urinary Cd on all‐cause mortality in the Japanese general population. A 19‐year cohort study was conducted in 1067 men and 1590 women aged 50 years or older who lived in three cadmium non‐polluted areas in Japan. The subjects were divided into four quartiles based on creatinine adjusted U‐Cd (µg g−1 cre). The hazard ratio (HR) and 95% confidence interval (CI) for continuous U‐Cd or the quartiles of U‐Cd were estimated for all‐cause mortality using a proportional hazards regression.The all‐cause mortality rates per 1000 person years were 31.2 and 15.1 in men and women, respectively. Continuous U‐Cd (+1 µg g−1 cre) was significantly related to the all‐cause mortality in men (HR 1.05, 95% CI: 1.02–1.09) and women (HR 1.04, 95% CI: 1.01–1.07). Furthermore in men, the third (1.96–3.22 µg g−1 cre) and fourth quartile (≥3.23 µg g−1 cre) of U‐Cd showed a significant, positive HR (third: HR 1.35, 95% CI: 1.03–1.77, fourth: HR 1.64, 95% CI: 1.26–2.14) for all‐cause mortality compared with the first quartile (<1.14 µg g−1 cre). In women, the fourth quartile of U‐Cd (≥4.66 µg g−1 cre) also showed a significant HR (1.49, 95% CI 1.11–2.00) for all‐cause mortality compared with the first quartile (<1.46 µg g−1 cre).In the present study, U‐Cd was significantly associated with increased mortality in the Japanese general population, indicating that environmental Cd exposure adversely affects the life prognosis in Cd non‐polluted areas in Japan. Copyright © 2014 John Wiley & Sons, Ltd.
Tl(I) and Tl(III) alter the expression of EGF‐dependent signals and cyclins required for pheochromocytoma (PC12) cell‐cycle resumption and progression
Authors: Pino María T. L. , Verstraeten Sandra V. 
Published: December 2014

AbstractThe effects of thallium [Tl(I) and Tl(III)] on the PC12 cell cycle were evaluated without (EGF−) or with (EGF+) media supplementation with epidermal growth factor (EGF). The following markers of cell‐cycle phases were analyzed: cyclin D1 (G1); E2F‐1, cyclin E and cytosolic p21 (G1→S transition); nuclear PCNA and cyclin A (S); and cyclin B1 (G2). The amount of cells in each phase and the activation of the signaling cascade triggered by EGF were also analyzed. Tl(I) and Tl(III) (5–100 μM) caused dissimilar effects on PC12 cell proliferation. In EGF− cells, Tl(I) increased the expression of G1→S transition markers and nuclear PCNA, without affecting cyclin A or cyclin B1. In addition to those, cyclin B1 was also increased in EGF+ cells. In EGF− cells, Tl(III) increased the expression of cyclin D1, all the G1→S and S phase markers and cyclin B1. In EGF+ cells, Tl(III) increased cyclin D1 expression and decreased all the markers of G1→S transition and the S phase. Even when these cations did not induce the activation of EGF receptor (EGFR) in EGF− cells, they promoted the phosphorylation of ERK1/2 and Akt. In the presence of EGF, the cations anticipated EGFR phosphorylation without affecting the kinetics of EGF‐dependent ERK1/2 and Akt phosphorylation. Altogether, results indicate that Tl(I) promoted cell proliferation in both EGF− and EGF+ cells. In contrast, Tl(III) promoted the proliferation of EGF− cells but delayed it in EGF+ cells, which may be related to the toxic effects of this cation in PC12 cells. Copyright © 2014 John Wiley & Sons, Ltd.
PTH Signaling During Exercise Contributes to Bone Adaptation
Authors: Gardinier Joseph D , Mohamed Fatma , Kohn David H 
Published: December 2014

ABSTRACT

Improving the structural integrity of bone reduces fracture risk and development of osteoporosis later in life. Exercise can increase the mechanical properties of bone, and this increase is often attributed to the dynamic loading created during exercise. However, the increase in systemic parathyroid hormone (PTH) levels during exercise gives reason to hypothesize that PTH signaling also regulates bone adaptation in response to exercise. Therefore, the first aim of this study was to establish the impact PTH signaling has on bone adaptation during exercise by inhibiting PTH signaling with PTH(7-34); the second aim was to determine whether increasing PTH levels during exercise with PTH(1-34) can augment bone adaptation. Thirty minutes after a single bout of running on a treadmill, mice exhibited a twofold increase in systemic PTH levels. Under the same exercise regimen, the influence of PTH signaling on bone adaptation during exercise was then evaluated in mice after 21 consecutive days of exercise and treatment with PTH(7-34), PTH(1-34), or vehicle. Exercise alone caused a significant increase in trabecular bone volume with adaptation to a more platelike structure, which was inhibited with PTH(7-34) during exercise. Changes in structural-level and tissue-level mechanical properties during exercise occurred in the absence of significant changes to cortical bone geometry. Inhibition of PTH signaling during exercise attenuated the changes in structural-level mechanical properties, but not tissue-level properties. Enhanced PTH signaling during exercise with PTH(1-34) increased trabecular and cortical bone volume, but had little effect on the structural-level and tissue-level mechanical properties compared to exercise alone. Our study is the first to demonstrate that bone adaptation during exercise is not only a function of dynamic loading, but also PTH release, and that PTH signaling contributes differently at the structural and tissue levels. © 2015 American Society for Bone and Mineral Research.
Bone Volume Fraction and Fabric Anisotropy Are Better Determinants of Trabecular Bone Stiffness Than Other Morphological Variables
Authors: Maquer Ghislain , Musy Sarah N , Wandel Jasmin , Gross Thomas , Zysset Philippe K 
Published: December 2014

ABSTRACT

As our population ages, more individuals suffer from osteoporosis. This disease leads to impaired trabecular architecture and increased fracture risk. It is essential to understand how morphological and mechanical properties of the cancellous bone are related. Morphology-elasticity relationships based on bone volume fraction (BV/TV) and fabric anisotropy explain up to 98% of the variation in elastic properties. Yet, other morphological variables such as individual trabeculae segmentation (ITS) and trabecular bone score (TBS) could improve the stiffness predictions. A total of 743 micro–computed tomography (μCT) reconstructions of cubic trabecular bone samples extracted from femur, radius, vertebrae, and iliac crest were analyzed. Their morphology was assessed via 25 variables and their stiffness tensor (CFE) was computed from six independent load cases using micro finite element (μFE) analyses. Variance inflation factors were calculated to evaluate collinearity between morphological variables and decide upon their inclusion in morphology-elasticity relationships. The statistically admissible morphological variables were included in a multiple linear regression model of the dependent variable CFE. The contribution of each independent variable was evaluated (ANOVA). Our results show that BV/TV is the best determinant of CFE(r2adj = 0.889), especially in combination with fabric anisotropy (r2adj = 0.968). Including the other independent predictors hardly affected the amount of variance explained by the model (r2adj = 0.975). Across all anatomical sites, BV/TV explained 87% of the variance of the bone elastic properties. Fabric anisotropy further described 10% of the bone stiffness, but the improvement in variance explanation by adding other independent factors was marginal (&lt;1%). These findings confirm that BV/TV and fabric anisotropy are the best determinants of trabecular bone stiffness and show, against common belief, that other morphological variables do not bring any further contribution. These overall conclusions remain to be confirmed for specific bone diseases and postelastic properties. © 2015 American Society for Bone and Mineral Research.
MicroRNA-140 Provides Robustness to the Regulation of Hypertrophic Chondrocyte Differentiation by the PTHrP-HDAC4 Pathway
Authors: Papaioannou Garyfallia , Mirzamohammadi Fatemeh , Lisse Thomas S , Nishimori Shigeki , Wein Marc N , Kobayashi Tatsuya 
Published: December 2014

ABSTRACT

Growth plate chondrocytes go through multiple differentiation steps and eventually become hypertrophic chondrocytes. The parathyroid hormone (PTH)-related peptide (PTHrP) signaling pathway plays a central role in regulation of hypertrophic differentiation, at least in part, through enhancing activity of histone deacetylase 4 (HDAC4), a negative regulator of MEF2 transcription factors that drive hypertrophy. We have previously shown that loss of the chondrocyte-specific microRNA (miRNA), miR-140, alters chondrocyte differentiation including mild acceleration of hypertrophic differentiation. Here, we provide evidence that miR-140 interacts with the PTHrP-HDAC4 pathway to control chondrocyte differentiation. Heterozygosity of PTHrP or HDAC4 substantially impaired animal growth in miR-140 deficiency, whereas these mutations had no effect in the presence of miR-140. miR-140–deficient chondrocytes showed increased MEF2C expression with normal levels of total and phosphorylated HDAC4, indicating that the miR-140 pathway merges with the PTHrP-HDAC4 pathway at the level of MEF2C. miR-140 negatively regulated p38 mitogen-activated protein kinase (MAPK) signaling, and inhibition of p38 MAPK signaling reduced MEF2C expression. These results demonstrate that miR-140 ensures the robustness of the PTHrP/HDAC4 regulatory system by suppressing MEF2C-inducing stimuli. © 2014 American Society for Bone and Mineral Research © 2015 American Society for Bone and Mineral Research
Downregulation of Connexin 32 Attenuates Hypoxia/Reoxygenation Injury in Liver Cells
Authors: Wang Ren , Huang Fei , Chen Zhangyan , Li Shangrong 
Published: December 2014

ABSTRACTGap junction intercellular communication is involved in ischemia–reperfusion (IR) injury of organs. Connexins are proteins that are critical to the function of gap junctions. To clarify the role of gap junctions in IR injury in liver cells, the function of gap junctions was modulated in an in vitro hypoxia/reoxygenation (H/R) model. BRL‐3A rat liver cells, endogenously expressing connexins Cx32 and Cx43, were used to model the process of hepatic IR injury. Suppression of gap junction activity was achieved genetically, using Cx32‐specific small interfering RNA (siRNA), or chemically, with pharmacological inhibitors, oleamide, and 18‐α‐GA. BRL‐3A cells subjected to H/R exhibited reduced cell survival and pathologies indicative of IR injury. Cx32‐specific siRNA, oleamide, and 18‐α‐GA, respectively, decreased gap junction permeability, as assessed by the parachute assay. Pretreatment with Cx32‐specific siRNA increased cell survival. Pretreatment with oleamide or 18‐α‐GA did not improve cell survival. Modulating gap junction by Cx32 gene silencing protected BRL‐3A liver cells from H/R.
Categories That Should Be Removed From Mental Disorders Classifications: Perspectives and Rationales of Clinicians From Eight Countries
Authors: Robles Rebeca , Fresán Ana , Medina‐Mora María Elena , Sharan Pratap , Roberts Michael C. , de Jesus Mari Jair , Matsumoto Chihiro , Maruta Toshimasa , Gureje Oye , Ayuso‐Mateos José Luís , Xiao Zeping , Reed Geoffrey M. 
Published: December 2014

ObjectiveTo explore the rationales of mental health professionals (mainly psychiatrists and psychologists) from 8 countries for removing specific diagnostic categories from mental disorders classification systems.MethodAs part of a larger study, 505 participants indicated which of 60 major disorders should be omitted from mental disorders classification systems and provided rationales. Rationale statements were analyzed using inductive content analysis.ResultsThe majority of clinicians (60.4%) indicated that 1 or more disorders should be removed. The most common rationales were (a) problematic boundaries between normal and psychopathological conditions (45.9% of total removal recommendations), (b) problematic boundaries among mental disorders (25.4%), and (c) problematic boundaries between mental and physical disorders (24.0%). The categories most frequently recommended for deletion were gender identity disorder, sexual dysfunction, and paraphilias, usually because clinicians viewed these categories as being based on stigmatization of a way of being and behaving. A range of neurocognitive disorders were described as better conceptualized as nonpsychiatric medical conditions. Results were analyzed by country and country income level. Although gender identity disorder was the category most frequently recommended for removal overall, clinicians from Spain, India, and Mexico were most likely to do so and clinicians from Nigeria and Japan least likely, probably because of social and systemic factors that vary by country. Systematic differences in removal rationales by country income level may be related to the development, structure, and functioning of health systems.ConclusionImplications for development and dissemination of the classification of mental and behavioral disorders in WHO's ICD‐11 are discussed.