bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation and Characterisation of Dinuclear Nickel(II) Complexes Containing N3Ni(μ1,3‐SO3R)2(μ‐O2CR)NiN3 Cores: Crystal Structures and Magnetic Properties of [Ni2(L2)(O2CCH3)]BPh4 and [Ni2(L2)(O2CPh)]BPh4 [H2L2 = Macrocyclic Ligand with a N6(SO3)2 Donor Set]
Authors: Lach Jochen , Hahn Torsten , Kersting Berthold , Kortus Jens 
Published: March 2012

AbstractThe preparation and characterisation of two new macrocyclic NiII complexes containing N3Ni(μ1,3‐SO3R)2(μ‐O2CR)NiN3 cores are described. Complexes [Ni2(L2)(O2CMe)]+ (4) and [Ni2(L2)(O2CPh)]+ (5), where (L2)2– represents a macrocyclic hexaaza‐bis(phenylsulfonato) ligand, were synthesised by H2O2 oxidation of the respective parent complexes, [Ni2(L1)(O2CMe)]+ (1) and [Ni2(L1)(O2CPh)]+ (2), supported by the corresponding hexaaza‐bis(thiophenolate) macrocycle(L1)2–. The compounds were characterised by means of elemental analysis, mass spectrometry, IR and UV/Vis spectroscopy. The crystal structures of the tetraphenylborate salts of 4 and 5 show that the bridging thiophenolato functions in 1 and 2 are in both cases converted to μ1,3‐bridging sulfonato groups. The conversion to the sulfonato groups is accompanied by a drastic increase of the Ni···Ni distance from 3.483(1) Å in 1 and 3.491(1) Å in 2 to 4.543(1) Å in 4 and 4.5725(8) Å in 5. The magnetic properties are also affected. In contrast to 1 and 2, which exhibit an intramolecular ferromagnetic exchange interaction (S = 2 ground state), the spins of the nickel(II) (Si = 1 ions) in 4 and 5 are weakly antiferromagnetically coupled, the coupling constants J (H = –2JS1S2) being –2.0 cm–1 (4) and –2.3 cm–1 (5), to produce a diamagnetic (S = 0) ground state. Supporting DFT (density functional theory) calculations substantiate the experimental results.
3,5‐Dimethylpyrazole Derivatives of (Hydrido)chlorosilanes
Authors: Bitto Florian , Wagler Jörg , Kroke Edwin 
Published: March 2012

AbstractTetrachlorosilane, trichlorosilane and dichlorosilane react with 1‐trimethylsilyl‐3,5‐dimethylpyrazole (Me3Sipz*), triethylamine/3,5‐dimethylpyrazole (Hpz*) or solely Hpz* to afford the new silicon‐based scorpionate analogues X4–nSi(pz*)n (1 n = 4; 2 X = Cl, n = 3; 3 X = H, n = 3; 4 X = H, n = 2) and the ionic complex [H2Si(Hpz*)4]Cl2 (5). Compounds 1 and 2 are involved in a complex system of equilibria of both Si–Cl vs. Si–N dismutation and intramolecular Si–N exchange. The Si–H bonds in 3 and 4 remain intact, thus intermolecular exchange phenomena like that in compounds Cl4–nSi(pz*)n were not observed. 29Si NMR and Raman spectra indicate that 4 forms oligomers with hexacoordinate Si atoms in solution as well as in the solid state. The Si atom of 5 is also hexacoordinate in the solid state. However, the coordination mode in 5 is completely different to that in 1–4, because all four Hpz* ligands coordinate by using the available nitrogen lone pairs.
Unprecedented Transformation of Diiron Bridging Vinyliminium Ligands into Carboxyamido‐ and Alkylphosphonate‐Vinylalkylidenes
Authors: Marchetti Fabio , Zacchini Stefano , Zanotti Valerio 
Published: March 2012

AbstractThe vinyliminium complexes [Fe2{μ‐η1:η3‐C(R′)=C(R′)C=N(Me)(R)}(μ‐CO)(CO)(Cp)2][SO3CF3] (R = Me, R′ = CO2Me, 6a; R = R′ = Me, 6b; R = Me, R′ = Et, 6c; R = Xyl, R′ = CO2Me, 6d; R = Xyl, R′ = Me, 6e; Xyl = 2,6‐Me2C6H3) upon treatment with NaH in thf fragmented to afford the metallacyclopentadienone complexes [Fe(CO)(Cp){CN(Me)(R)C(R′)C(R′)C(O)}] (7a–7e). When the reaction of 6c with NaH was carried with thf direct from the bottle (i.e., not freshly distilled), the product was the vinylalkylidene complex[Fe2{μ‐η1:η3‐C(Et)C{C(O)NMe2}C(H)(Me)}(μ‐CO)(CO)(Cp)2] (8), which contains a carboxyamido group. The formation of 8 implies deprotonation of the bridging ligand and oxygen addition to the iminium carbon of 6c with rearrangement of the bridging coordination. Reaction of the vinyliminium complexes [Fe2{μ‐η1:η3‐C(R′)=C(R″)C=N(Me)(R)}(μ‐CO)(CO)(Cp)2][SO3CF3] (R = Me, R′ = R″ = CO2Me, 6a; R = R′ = Me, R″ = H, 6f; R = R′ = Me, R″ = H, 6g; R = Xyl, R = CH2Ph, R′ = CO2Me, R″ = H, 6h) with NaH and P(OMe)3 afforded the corresponding alkylphosphonate‐vinylalkylidene complexes [Fe2{μ‐η1:η3‐C(R′)C(R″)C{P(O)(OMe)2}N(Me)(R)}(μ‐CO)(CO)(Cp)2] (9a–9d). The reaction can be considered an Arbuzov‐like rearrangement involving an iminium group. The crystal structures of 8 and 9c were determined X‐ray diffraction.
Biomagnification of mercury through the benthic food webs of a temperate estuary: Masan Bay, Korea
Authors: Kim Eunhee , Kim Hyunji , Shin Kyung-hoon , Kim Min-seob , Kundu Sampa Rani , Lee Byeong-gweon , Han Seunghee 
Published: March 2012

Abstract
The authors examined food web magnification factors of total mercury (THg) and methylmercury (MeHg) for the benthic organisms in Masan Bay, a semiclosed, temperate estuary located on the southeastern coast of Korea. For benthic invertebrates, concentrations of THg and MeHg (%MeHg) ranged from 9.57 to 195 and 2.56 to 111 ng/g dry weight (12.2–85.6%), respectively. Benthic fish THg and MeHg (%MeHg) concentrations ranged widely from 10.8 to 618 and 2.90 to 529 ng/g dry weight (22.9–93.9%), respectively. The linear regression slopes of log [Hg] relative to δ15N (i.e., food web magnification factors) found for the Masan Bay benthic organisms were 0.119 for THg and 0.168 for MeHg. These values are similar to the food web magnification factors of benthic organisms and lower than those of pelagic organisms of various coastal marine environments. It suggests that pelagic organisms might be at greater risk of THg and MeHg accumulation than benthic biota. Environ. Toxicol. Chem. 2012;31:1254–1263. © 2012 SETAC
Toxicity of major cations and anions (Na+, K+, Ca2+, Cl−, and SO 42−) to a macrophyte and an alga
Authors: Simmons Jeffrey A. 
Published: March 2012

Abstract
In many freshwater systems around the world, the concentrations of major ions (Na+, K+, Ca2+, Mg2+, Cl−, HCO 3−, CO 32−, and SO 42−) are exhibiting increasing trends, approaching the concentrations historically found mainly in estuaries. The objectives of the present study were to determine at what concentrations these salts are toxic to an aquatic plant and a green alga, to investigate two potential mechanisms of toxicity, and to determine the usefulness of conductivity as an indicator of salt toxicity. In a series of laboratory trials, Lemna minor and Pseudokirchneriella subcapitata were exposed to a range of concentrations of five different salts. Conductivity levels that caused 10 or 50% reductions in growth-related traits (EC10 and EC50, respectively) were determined, using conductivity of the test solutions as the independent variable. The EC10 values ranged from 0.44 to 2.67 mS/cm for P. subcapitata and from 1.3 to &gt;19 mS/cm for L. minor. The EC50 values ranged from 1.7 to 5.8 mS/cm for P. subcapitata and from 4.2 to &gt;27 mS/cm for L. minor. For both species the EC values varied dramatically among the salts. Pseudokirchneriella subcapitata was most sensitive to KCl and NaCl, whereas L. minor was most sensitive to Na2SO4. The mechanism of toxicity does not appear to be related to production of reactive oxygen species, nor to reduction in chlorophyll concentrations. Because toxicity was strongly influenced by salt composition, regulation and management of specific ions may be preferable to conductivity. Environ. Toxicol. Chem. 2012;31:1370–1374. © 2012 SETAC
Diagnosis of potential stressors adversely affecting benthic communities in New Bedford Harbor, MA (USA)
Authors: Ho Kay T , Pelletier Marguerite C , Campbell Daniel E , Burgess Robert M , Johnson Roxanne L , Rocha Kenneth J 
Published: March 2012

Abstract
Diagnosing the causes of impaired ecosystems in the marine environment is critical for effective management action. When ecological impairment is based on toxicological or biological criteria (i.e., degraded benthic community composition or toxicity test results), managers are faced with the additional problem of diagnosing the cause of impairment before plans can be initiated to reduce the pollutant loading. We evaluated a number of diagnostic tools to determine their ability to identify pollutants in New Bedford Harbor (NBH), Massachusetts (USA), using a modified version of the US Environmental Protection Agency's (USEPA) stressor identification (SI) guidance. In this study, we linked chemical sources and toxic chemicals in the sediment with spatial concentration studies; we also linked toxic chemicals in the sediment with toxicity test results using toxicity identification and evaluation (TIE) studies. We used geographical information systems (GIS) maps to determine sources and to aid in determining spatially integrated inorganic nitrogen (SIIN). The SIIN values of reference and test estuaries were quantified and compared. Using this approach, we determined that toxic chemicals continue to be active stressors in NBH and that a moderate nutrient stress exists, but we were unable to link the nutrient stressor with a source. Also excess sedimentation was evaluated, but it does not appear to be an active stressor in this harbor. The research included an evaluation of the effectiveness of tools under development that may be used to evaluate stressors in water bodies. We found that the following tools were useful in diagnosing active stressors: toxicity tests, toxicity identification and evaluation (TIE) methods, comparison of grain size-normalized total organic carbon (TOC) ratios with reference sites, and comparison of SIIN with reference sites. This approach allowed us to successfully evaluate stressors in NBH retrospectively; however, a limitation in using retrospective data sets is that the approach may underestimate current or newly emerging stressors. Integr Environ Assess Manag 2012; 8: 685–702. © 2012 SETAC
Meat consumption, heterocyclic amines and colorectal cancer risk: The Multiethnic Cohort Study
Authors: Ollberding Nicholas J. , Wilkens Lynne R. , Henderson Brian E. , Kolonel Laurence N. , Le Marchand Loïc 
Published: March 2012

AbstractGreater consumption of red and processed meat has been associated with an increased risk of colorectal cancer in several recent meta‐analyses. Heterocyclic amines (HCAs) have been hypothesized to underlie this association. In this prospective analysis conducted within the Multiethnic Cohort Study, we examined whether greater consumption of total, red or processed meat was associated with the risk of colorectal cancer among 165,717 participants who completed a detailed food frequency questionnaire at baseline. In addition, we examined whether greater estimated intake of HCAs was associated with the risk of colorectal cancer among 131,763 participants who completed a follow‐up questionnaire that included a meat‐cooking module. A total of 3,404 and 1,757 invasive colorectal cancers were identified from baseline to the end of follow‐up and from the date of administration of the meat‐cooking module to the end of follow‐up, respectively. Proportional hazard models were used to estimate basic and multivariable‐adjusted relative risks (RRs) and 95% confidence intervals for colorectal cancer associated with dietary exposures. In multivariable models, no association with the risk of colorectal cancer was detected for density‐adjusted total meat (RRQ5 vs. Q1 = 0.93 [0.83–1.05]), red meat (RR = 1.02 [0.91–1.16]) or processed meat intake (RR = 1.06 [0.94–1.19]) or for total (RR = 0.90 [0.76–1.05]) or specific HCA intake whether comparing quintiles of dietary exposure or using continuous variables. Although our results do not support a role for meat or for HCAs from meat in the etiology of colorectal cancer, we cannot rule out the possibility of a modest effect.
Perifosine sensitizes curcumin‐induced anti‐colorectal cancer effects by targeting multiple signaling pathways both in vivo and in vitro
Authors: Chen Min‐Bin , Wu Xiao‐Yang , Tao Guo‐Qing , Liu Chao‐Ying , Chen Jian , Wang Li‐Qiang , Lu Pei‐Hua 
Published: March 2012

AbstractOur study shows that coadministration of curcumin and an orally bioactive alkylphospholipid perifosine results in a significant increase in colorectal cancer cell apoptosis and a marked inhibition of cell growth both in vitro and in vivo. This novel combinatorial regimen leads to changes of multiple cell signaling pathways including inactivation of Akt and nuclear factor‐κB as well as activation of c‐Jun N‐terminal kinases and endoplasmic reticulum stress. Further, perifosine and curcumin synergistically increase intracellular level of reactive oxygen species and ceramide, and downregulate the expression of cyclin D1 and Bcl‐2 in colorectal cancer cells. These changes at molecular level together account for the cancer cell apoptosis and growth inhibition. We conclude that perifosine sensitizes colorectal cancer cells to curcumin by modulating multiple signaling pathways. Adding perifosine with curcumin may represent an effective therapy regimen against colorectal cancers, and possible other aggressive tumors.
18F‐FDG‐PET evaluation of treatment response to neo‐adjuvant therapy in patients with locally advanced rectal cancer: A meta‐analysis
Authors: Zhang Chenpeng , Tong Jinlu , Sun Xiaoguang , Liu Jianjun , Wang Yuting , Huang Gang 
Published: March 2012

AbstractThe purpose of this meta‐analysis was to evaluate the utility of positron emission tomography (PET) using fluor‐18‐deoxyglucose (FDG) to predict the response of rectal cancer to neo‐adjuvant therapy. All previously published studies on the role of FDG‐PET in predicting the response of rectal cancer to neo‐adjuvant therapy were collected. Pooled sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated using statistical software. A total of 28 studies, comprising 1,204 patients with rectal cancer, were included in the meta‐analysis. Pooled sensitivity, specificity, PPV and NPV for FDG‐PET predicting the response to therapy was 78% [95% confidence interval (CI): 75–82%], 66% (95% CI: 62–69%), 70% (95% CI; 66–73%) and 75% (95% CI: 71–0.79%), respectively. The included studies were of a relatively high methodological quality according to the QUADAS (quality assessment of studies of diagnostic accuracy included in systematic reviews) criteria. Based on the subgroup analyses, there was no significant difference between the response index, the standardized uptake value and the visual response score in predicting the therapy response. However, the accuracy of the group that underwent PET scanning during therapy showed significantly higher values (sensitivity 86% and specificity 80%) than the group that was scanned after completion of the therapy. Therefore, FDG‐PET is valuable for predicting the response of rectal carcinoma to neo‐adjuvant therapy, and early evaluation of response during the therapy may be more promising. However, additional studies using prospective clinical trials will be required to assess the clinical benefit of this strategy.
Blockade of β1‐, β2‐ and β3‐adrenoceptors in the temporomandibular joint induces antinociception especially in female rats
Authors: Fávaro‐Moreira N.C. , Parada C.A. , Tambeli C.H. 
Published: March 2012

AbstractBackgroundTemporomandibular joint (TMJ) receives rich sympathetic innervations that may contribute to TMJ pain through the local release of sympathomimetic amines. The aim of this study was to determine whether blockade of β‐adrenoceptors in the TMJ of male and female rats reduces formalin‐induced TMJ nociceptive behaviour.MethodsWe co‐administrated each one of the selective β1‐, β2‐ and β3‐adrenoceptors antagonists, atenolol, ICI 118.551 and SR59230A, respectively, with formalin in the TMJ of male and proestrus and dioestrus female rats. Because intra‐temporomandibular joint formalin induces significantly different concentration‐dependent responses among the three groups, with dioestrus females showing greater responses than males or proestrus females, equi‐nociceptive formalin concentrations were used to test the effects of the β‐adrenoceptor antagonists.ResultsWe found that atenolol, ICI 118.551 and SR59230A significantly reduced formalin‐induced TMJ nociception in a dose response fashion in both males and females. However, a lower dose of each β‐adrenoceptor antagonist was sufficient to significantly reduce nociceptive responses in females than in males. Administration of the highest doses of each β‐adrenoceptor antagonist in the TMJ contralateral to that receiving formalin did not affect formalin‐induced nociception in males and females, confirming the local action of the β‐adrenoceptor antagonists.ConclusionsWe conclude that blockade of β‐adrenoceptors in the temporomandibular joint suppresses formalin‐induced TMJ nociceptive behaviour in both males and females but females are more responsive. These findings suggest that the use of β‐blockers in the treatment of TMJ pain might be of benefit, especially in females.
Aging of porous silicon in physiological conditions: Cell adhesion modes on scaled 1D micropatterns
Authors: Noval Alvaro Muñoz , Vaquero Vanessa Sánchez , Quijorna Esther Punzón , Costa Vicente Torres , Pérez Darío Gallach , Méndez Laura González , Montero Isabel , Palma Raul J. Martín , Font Aurelio Climent , Ruiz Josefa P. García , Silván Miguel Manso 
Published: March 2012

AbstractThe surface properties of porous silicon (PSi) evolve rapidly in phosphate‐buffered saline. X‐ray photoelectron spectra indicate the formation of a Si–OH and C–O enriched surface, which becomes increasingly hydrophilic with aging time. Multiscale stripe micropatterns of Si and PSi have been fabricated by means of a high‐energy ion‐beam irradiation process. These micropatterns have been aged in physiological conditions and used to analyze human mesenchymal stem cell (hMSC) adhesion. The actin cytoskeleton of hMSCs orients following the uniaxial micropatterns. In the wider Si stripes, hMSCs are dominantly located on Si areas. However, for reduced Si widths, adhesion is avoided on PSi by a split assembly of the actin cytoskeleton on two parallel Si areas. These results confirm that nanostructured Si–OH/C–O‐rich surfaces with hydrophilic character are specially adapted for the creation of cell adhesion surface contrasts. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 2012.
Beta‐tricalcium phosphate particles as a controlled release carrier of osteogenic proteins for bone tissue engineering
Authors: Hu Junli , Hou Yaping , Park Hyejin , Lee Min 
Published: March 2012

AbstractBeta‐tricalcium phosphate (β‐TCP) has been widely used as bone substitutes and delivery carriers of osteogenic proteins. However, low protein carrying capacity and agent burst release profiles of β‐TCP limit their usage. This study investigates strategies to enhance protein carrying capacity of β‐TCP particles with reduced initial burst by surface etching in citric acid solution or by creating apatite coatings with the simulate body fluid immersion approach. The release kinetics of protein from the modified β‐TCP particles was investigated using Nel‐like molecule‐1 (Nell‐1), a novel osteogenic protein, as a model protein. Although chemical etching treatments reduced the initial burst release of protein from the particles, a rapid burst release was observed with high protein dose. In contrast, the burst release of protein was significantly reduced by the apatite coating and a high protein dose was successfully delivered over a prolonged period from the apatite‐coated particles. Protein release was further modulated by simultaneously delivering proteins from two different substrates: acid‐etched and apatite‐coated particles. The bioactivity of the protein was preserved during the loading procedure onto the particles. In addition, protein‐loaded particles maintained biological activity in the lyophilized state over 4 weeks. These findings suggest that the protein carrying capacity of β‐TCP can be modulated by surface modification, which has a potential for use as a protein carrier with controlled release. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012.
New ureteral scaffold constructed with composite poly(L‐lactic acid)–collagen and urothelial cells by new centrifugal seeding system
Authors: Fu Wei‐Jun , Xu Yong‐De , Wang Zhong‐Xin , Li Gang , Shi Jian‐Guo , Cui Fu‐Zhai , Zhang Yuanyuan , Zhang Xu 
Published: March 2012

AbstractA tissue‐engineered ureteral scaffold was constructed with composited poly L‐lactic acid (PLLA)–collagen endoluminal stent and uroepithelial cells (UECs) using a new seeding system. The electrospun PLLA–collagen nanofibrous mesh was seeded efficiently with human ureteral epithelial cells using a modified centrifugal seeding device. The cellular nanofibrous mesh was then wound around a spiral endoluminal stent to form a cellular composited PLLA–collagen ureteral scaffold. The cellular ureteral scaffold was subcutaneously implanted into nude mice. Cell attachment, distribution, and viability in vitro were investigated along with the cell fate in vivo. (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) assay showed that scaffolds seeded with centrifugal method had higher cellular activity than scaffolds seeded with static method (p < 0.05), and the metabolic activity per cell had no significant differences between the two methods (p > 0.05). Histologic analysis showed that the entrapped UECs remained in the scaffolds after 2 wk of implantation. The results of the study indicated that the composited PLLA–collagen endoluminal stent could serve as alternative cell carrier for tissue engineering ureter. In addition, the new modified centrifugal seeding system allowed rapid homogeneous distribution of cells onto the nanofibrous mesh, which will be useful to ureteral reconstruction. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012.
Effect of deposition parameters on the photocatalytic activity and bioactivity of TiO2 thin films deposited by vacuum arc on Ti‐6Al‐4V substrates
Authors: Lilja Mirjam , Welch Ken , Åstrand Maria , Engqvist Håkan , Strømme Maria 
Published: March 2012

AbstractThis article evaluates the influence of the main parameters in a cathodic arc deposition process on the microstructure of titanium dioxide thin coatings and correlates these to the photocatalytic activity (PCA) and in vitro bioactivity of the coatings. Bioactivity of all as deposited coatings was confirmed by the growth of uniform layers of hydroxyapatite (HA) after 7 days in phosphate buffered saline at 37°C. Comparison of the HA growth after 24 h indicated enhanced HA formation on coatings with small titanium dioxide grains of rutile and anatase phase. The results from the PCA studies showed that coatings containing a mixed microstructure of both anatase and rutile phases, with small grain sizes in the range of 26–30 nm and with a coating thickness of about 250 nm, exhibited enhanced activity as compared with other microstructures and higher coating thickness. The results of this study should be valuable for the development of new bioactive implant coatings with photocatalytically induced on‐demand antibacterial properties. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Patterns of endorhizal fungal associations in fruit crops of southern India
Authors: Jaison Sarah , Rajeswari Krishnasamy , Muthukumar Thangavelu 
Published: March 2012

AbstractA survey on the endorhizal status of 39 fruit crops of 25 families, indicated that 22 fruit crops had arbuscular mycorrhizal (AM)–, four had dark septate endophyte (DSE)–fungal association, and 13 had dual colonization of AM and DSE fungi. Fruit crops were capable of forming Arum‐, Paris‐, or intermediate‐types of AM morphologies of which intermediate‐type was common. To our knowledge, we report for the first time AM in 10 fruit crops and DSE‐fungal association in 17 fruit crops. The extent of AM‐ and DSE‐fungal colonization ranged from 41% to 98% and < 1% to 89.9%, respectively, in different fruit crops. Arbuscular mycorrhizal–fungal spore numbers in the rhizosphere ranged from 6 to 61 spores per 25 g of soil. Arbuscular mycorrhizal–fungal spores belonging to Acaulospora, Glomus, and Scutellospora were isolated from the rhizosphere soil.