bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of High Frequency Sensors for Contactless Monitoring in Disposable Bioreactors
Authors: Nacke Thomas , Barthel Andreas , Frense Dieter , Meister Matthias , Cahill Brian P.
Published: November 2012

Contamination‐free process measurement is essential for efficient monitoring of fermenters. This contribution introduces the use of high‐frequency sensors for the contactless measurement of the permittivity and conductivity of fermentation media. As microwaves can penetrate through plastic materials without much attenuation, it is possible to achieve measurement setups that can measure the media under test without any direct contact and with long‐term stability. The sensor can be installed directly to the outer surface of the fermenter or can be clamped onto tubing.
Prognostic impact of the isocitrate dehydrogenase 1 single‐nucleotide polymorphism rs11554137 in malignant gliomas
Authors: Wang Xiao‐Wei , Boisselier Blandine , Rossetto Marta , Marie Yannick , Idbaih Ahmed , Mokhtari Karima , Gousias Konstantinos , Hoang‐Xuan Khê , Delattre Jean‐Yves , Simon Matthias , Labussière Marianne , Sanson Marc
Published: November 2012

BACKGROUND.

The IDH1 gene, which encodes isocitrate dehydrogenase 1, is frequently mutated in gliomas and acute myeloid leukemia. The single‐nucleotide polymorphism (SNP) (reference SNP no. rs11554137:C>T) located on IDH1 codon 105 has been associated with a poor outcome in patients with acute myeloid leukemia but has not been investigated in patients with gliomas.

METHODS.

The IDH1 codon 105 SNP was genotyped first in a series of 952 patients with grade 2 through 4 gliomas and was correlated with outcomes and tumor genomic profile. Then, it was genotyped in 2 validations sets of 306 patients with glioblastoma (GBM) and 591 patients with glioma.

RESULTS.

The minor allele codon 105 glycine (GGT) SNP (IDH1105GGT) was identified in 98 of 952 patients (10.3%) and was not associated with the codon 132 (IDH1132) mutation. Patients who had GMB with the IDH1105GGT variant had a poorer outcome than patients without the variant (median overall survival [OS], 10.7 months vs 15.5 months; P = .001; median progression‐free survival [PFS], 6.4 months vs 8.5 months; P = .003). The prognostic impact was confirmed in an independent validation set of 306 GBMs from the same center (median PFS, 6.8 months vs 9.7 months; P = .006; median OS, 13.9 months vs 18.8 months; P = .0187). In the second validation cohort (591 grade 2‐4 gliomas), a significant association was observed between IDH1105GGT and an adverse prognosis for the overall series and for patients with World Health Organization grade 3 gliomas, but the difference did not reach significance in patients with GBM.

CONCLUSIONS.

Taken together, the current data strongly suggested an association between the SNP rs11554137:C>T polymorphism and adverse outcomes in patients with malignant glioma. A single‐nucleotide polymorphism (SNP) located on codon 105 of the isocitrate dehydrogenase 1 (IDH1) gene (reference SNP rs11554137) is analyzed in 3 independent series of patients with gliomas. The SNP rs11554137 is independent of the occurrence of somatic mutation on IDH1 codon 132, but, per se, has a prognostic impact in malignant gliomas. Cancer 2013. © 2012 American Cancer Society.
Cost‐effectiveness of alternating magnetic resonance imaging and digital mammography screening in BRCA1 and BRCA2 gene mutation carriers
Authors: Cott Chubiz Jessica E. , Lee Janie M. , Gilmore Michael E. , Kong Chung Y. , Lowry Kathryn P. , Halpern Elkan F. , McMahon Pamela M. , Ryan Paula D, , Gazelle G. Scott
Published: November 2012

BACKGROUND:

Current clinical guidelines recommend earlier, more intensive breast cancer screening with both magnetic resonance imaging (MRI) and mammography for women with breast cancer susceptibility gene (BRCA) mutations. Unspecified details of screening schedules are a challenge for implementing guidelines.

METHODS:

A Markov Monte Carlo computer model was used to simulate screening in asymptomatic women who were BRCA1 and BRCA2 mutation carriers. Three dual‐modality strategies were compared with digital mammography (DM) alone: 1) DM and MRI alternating at 6‐month intervals beginning at age 25 years (Alt25), 2) annual MRI beginning at age 25 years with alternating DM added at age 30 years (MRI25/Alt30), and 3) DM and MRI alternating at 6‐month intervals beginning at age 30 years (Alt30). Primary outcomes were quality‐adjusted life years (QALYs), lifetime costs (in 2010 US dollars), and incremental cost‐effectiveness (dollars per QALY gained). Additional outcomes included potential harms of screening, and lifetime costs stratified into component categories (screening and diagnosis, treatment, mortality, and patient time costs).

RESULTS:

All 3 dual‐modality screening strategies increased QALYs and costs. Alt30 screening had the lowest incremental costs per additional QALY gained (BRCA1, $74,200 per QALY; BRCA2, $215,700 per QALY). False‐positive test results increased substantially with dual‐modality screening and occurred more frequently in BRCA2 carriers. Downstream savings in both breast cancer treatment and mortality costs were outweighed by increases in up‐front screening and diagnosis costs. The results were influenced most by estimates of breast cancer risk and MRI costs.

CONCLUSIONS:

Alternating MRI and DM screening at 6‐month intervals beginning at age 30 years was identified as a clinically effective approach to applying current guidelines, and was more cost‐effective in BRCA1 gene mutation carriers compared with BRCA2 gene mutation carriers. Cancer 2013. © 2012 American Cancer Society.
Human papillomavirus vaccine uptake among 18‐ to 26‐year‐old women in the United States
Authors: Laz Tabassum H. , Rahman Mahbubur , Berenson Abbey B.
Published: November 2012

BACKGROUND:

Human papillomavirus (HPV) vaccine uptake among young adult women has been reported to be very low. The authors conducted this study to provide an update on HPV vaccine uptake among 18‐ to 26‐year‐old women.

METHODS:

The authors used the National Health Interview Survey 2010 data to estimate HPV vaccine coverage and their correlates.

RESULTS:

Overall, 22.7% of women initiated (≥1 dose) and 12.7% completed the vaccine (≥3 doses). Thus, about 56% of women who initiated the vaccine completed it. Multivariate logistic regression analyses showed that younger age, unmarried status, Papanicolaou test, influenza vaccine, lifetime vaccines, and HPV vaccine awareness were positively associated with receiving ≥1 and ≥3 doses. In addition, uninsured women were less likely to receive ≥1 dose (odds ratio [OR], 0.49; 95% confidence interval [CI], 0.28‐0.84), and blacks (OR, 0.48; 95% CI, 0.23‐0.99) and women with a family income <100% of the federal poverty level (OR, 0.40; 95% CI, 0.21‐0.73) were less likely to receive ≥3 doses. Furthermore, based on vaccine initiators, blacks were less likely than whites to complete the vaccine (OR, 0.29; 95% CI, 0.16‐0.55). Two thirds of unvaccinated women were not interested in future vaccination. Among those who were interested, >76.4% preferred to receive it free or at a lower cost, whereas 20% would pay the full cost of the vaccine.

CONCLUSIONS:

One in 8 women completed the 3‐dose HPV vaccine. Educational and vaccine financing programs are needed to improve the uptake among low‐income minority women who are at increased risk for cervical cancer. Cancer 2013. © 2012 American Cancer Society.
Postsynaptic muscarinic m2 receptors at cholinergic and glutamatergic synapses of mouse brainstem motoneurons
Authors: Csaba Zsolt , Krejci Eric , Bernard Véronique
Published: November 2012

In many brain areas, few cholinergic synapses are identified. Acetylcholine is released into the extracellular space and acts through diffuse transmission. Motoneurons, however, are contacted by numerous cholinergic terminals, indicating synaptic cholinergic transmission on them. The muscarinic m2 receptor is the major acetylcholine receptor subtype of motoneurons; therefore, we analyzed the localization of the m2 receptor in correlation with synapses by electron microscopic immunohistochemistry in the mouse trigeminal, facial, and hypoglossal motor nuclei. In all nuclei, m2 receptors were localized at the membrane of motoneuronal perikarya and dendrites. The m2 receptors were concentrated at cholinergic synapses located on the perikarya and most proximal dendrites. However, m2 receptors at cholinergic synapses represented only a minority (<10%) of surface m2 receptors. The m2 receptors were also enriched at glutamatergic synapses in both motoneuronal perikarya and dendrites. A relatively large proportion (20–30%) of plasma membrane–associated m2 receptors were located at glutamatergic synapses. In conclusion, the effect of acetylcholine on motoneuron populations might be mediated through a synaptic as well as diffuse type of transmission. J. Comp. Neurol. 521:2008–2024, 2013. © 2012 Wiley Periodicals, Inc.
On the colours dichromats see
Authors: Logvinenko Alexander D.
Published: November 2012

Dichromatic colour vision is commonly believed to be a reduced form of trichromatic colour vision (referred to as the reductionist principle). In particular, the colour palette of the dichromats is believed to be a part of the colour palette of the trichromats. As the light‐colour palette differs from the object‐colour palette, the dichromatic colour palettes have been derived separately for light‐colours and object‐colours in this report. As to light‐colours, the results are in line with the widely accepted view that the dichromatic colour palettes contain only two hues. However, the dichromatic object‐colour palettes have proved to contain the same six component colours which constitute the trichromatic object‐colour palette (yellow, blue, red, green, black and white). Moreover, all the binary and tertiary combinations of the six component colours present in the trichromatic object‐colour palette also occur in the dichromatic object‐colour palettes. Yet, only five of the six component colours are experienced by dichromats as unitary (unique) object‐colours. The green unitary colour is absent in the dichromatic object‐colour palettes. The difference between the dichromatic and trichromatic object‐colour palettes arises from the fact that not every combination of the component‐colour magnitudes occurs in the dichromatic object‐colour palettes. For instance, in the dichromatic object‐colour palettes there is no colour with the strong green component colour. Furthermore, each achromatic (black or white) component colour of a particular magnitude is combined with the only combination of the chromatic components. In other words, the achromatic component colours are bound with the chromatic component combinations in dichromats. © 2012 Wiley Periodicals, Inc. Col Res Appl, 39, 112–124, 2014
Plasma Synthesis of Polymer‐Capped Dye‐Sensitised Anatase Nanopowders for Visible‐Light‐Driven Hydrogen Evolution
Authors: Kruth Angela , Hansen Sven , Beweries Torsten , Brüser Volker , Weltmann Klaus‐Dieter
Published: November 2012

Visible‐light‐driven photocatalysis is currently attracting a great deal of attention because of its potential application in solar water splitting. However, the development of efficient and durable catalyst systems is still a challenging problem. In Ru dye‐sensitised TiO2 nanopowders, catalyst performances are found to decline as a result of poor bonding of the dye molecule to the TiO2 surface and subsequent detachment and self‐aggregation of the dye. Our strategy to improve the stability of the dye–TiO2 interface is the encapsulation of the dye/TiO2 assembly in an amino‐group‐containing polyallylamine layer anchored to TiO2. A low‐pressure pulsed microwave discharge plasma polymerization process was employed to coat a commercial anatase nanopowder with a thin polyallylamine layer to nanoconfine the adsorbed dye molecules. Electron microscopy and UV/Vis spectroscopy was carried out to characterise the resulting encapsulated nanostructures. The long‐term stability of the new nanomaterial as the photoactive component of a water reduction catalyst system for H2 evolution investigated in a slurry reactor under visible‐light irradiation showed stable evolution rates over a period of several days.
Implication of hepatic stem cells in functional liver repopulation
Authors: Christ Bruno , Pelz Sandra
Published: November 2012

The liver has an enormous potential to restore the parenchymal tissue loss due to injury. This is accomplished by the proliferation of either the hepatocytes or liver progenitor cells in cases where massive damage prohibits hepatocytes from entering the proliferative response. Under debate is still whether hepatic stem cells are involved in liver tissue maintenance and regeneration or even whether they exist at all. The definition of an adult tissue‐resident stem cell comprises basic functional stem cell criteria like the potential of self‐renewal, multipotent, i.e. at least bipotent differentiation capacity and serial transplantability featuring the ability of functional tissue repopulation. The relationship between a progenitor and its progeny should exemplify the lineage commitment from the putative stem cell to the differentiated cell. This is mainly assessed by lineage tracing and immunohistochemical identification of markers specific to progenitors and their descendants. Flow cytometry approaches revealed that the liver stem cell population in animals is likely to be heterogeneous giving rise to progeny with different molecular signatures, depending on the stimulus to activate the putative stem cell compartment. The stem cell criteria are met by a variety of cells identified in the fetal and adult liver both under normal and injury conditions. It is the purpose of this review to verify hepatic stem cell candidates in the light of the stem cell definition criteria mentioned. Also from this point of view adult stem cells from non‐hepatic tissues such as bone marrow, umbilical cord blood or adipose tissue, have the potential to differentiate into cells featuring functional hepatocyte characteristics. This has great impact because it opens the possibility of generating hepatocyte‐like cells from adult stem cells in a sufficient amount and quality for their therapeutical application to treat end‐stage liver diseases by stem cell‐based hepatocytes in place of whole organ transplantation. © 2012 International Society for Advancement of Cytometry
Regulation of Primitive Hematopoiesis by Class I Histone Deacetylases
Authors: Shah Rishita R. , Koniski Anne , Shinde Mansi , Blythe Shelby A. , Fass Daniel M. , Haggarty Stephen J. , Palis James , Klein Peter S.
Published: November 2012

Background: Histone deacetylases (HDACs) regulate multiple developmental processes and cellular functions. However, their roles in blood development have not been determined, and in Xenopus laevis a specific function for HDACs has yet to be identified. Here, we employed the class I selective HDAC inhibitor, valproic acid (VPA), to show that HDAC activity is required for primitive hematopoiesis. Results: VPA treatment during gastrulation resulted in a complete absence of red blood cells (RBCs) in Xenopus tadpoles, but did not affect development of other mesodermal tissues, including myeloid and endothelial lineages. These effects of VPA were mimicked by Trichostatin A (TSA), a well‐established pan‐HDAC inhibitor, but not by valpromide, which is structurally similar to VPA but does not inhibit HDACs. VPA also caused a marked, dose‐dependent loss of primitive erythroid progenitors in mouse yolk sac explants at clinically relevant concentrations. In addition, VPA treatment inhibited erythropoietic development downstream of bmp4 and gata1 in Xenopus ectodermal explants. Conclusions: These findings suggest an important role for class I HDACs in primitive hematopoiesis. Our work also demonstrates that specific developmental defects associated with exposure to VPA, a significant teratogen in humans, arise through inhibition of class I HDACs. Developmental Dynamics 242:108–121, 2013. © 2012 Wiley Periodicals,Inc.
Degraded Environments Alter Prey Risk Assessment
Authors: Lönnstedt Oona M. , McCormick Mark I. , Chivers Douglas P.
Published: November 2012

Elevated water temperatures, a decrease in ocean pH, and an increasing prevalence of severe storms have lead to bleaching and death of the hard corals that underpin coral reef ecosystems. As coral cover declines, fish diversity and abundance declines. How degradation of coral reefs affects behavior of reef inhabitants is unknown. Here, we demonstrate that risk assessment behaviors of prey are severely affected by coral degradation. Juvenile damselfish were exposed to visual and olfactory indicators of predation risk in healthy live, thermally bleached, and dead coral in a series of laboratory and field experiments. While fish still responded to visual cues in all habitats, they did not respond to olfactory indicators of risk in dead coral habitats, likely as a result of alteration or degradation of chemical cues. These cues are critical for learning and avoiding predators, and a failure to respond can have dramatic repercussions for survival and recruitment.
Effect of Annealing Temperature on the Structural and Photoluminescence Properties of Y2Sn2O7:Eu Nanoparticles
Authors: Nigam Sandeep , Sudarsan Vasanthakumaran , Vatsa Rajesh Kumar
Published: November 2012

The structural and photoluminescence properties of Eu3+‐doped Y2Sn2O7 nanoparticles have been systematically studied as a function of heat treatment temperature. Crystalline Y2Sn2O7:Eu nanoparticles with sizes in the range of 2–5 nm were prepared at the relatively low temperature of 700 °C. Based on the Rietveld refinement of powder X‐ray diffraction patterns, it was confirmed that the YO8/EuO8 polyhedra in the Y2Sn2O7:Eu lattice become more symmetric as the annealing temperature increases. The extent of distortion of the YO8/EuO8 polyhedra is reflected in the luminescence parameters Ω2 and Ω4, which are a measure of the polarizability of Y–O and Eu–O bonds in the lattice. There are a significant number of surface Eu3+ ions in the nanoparticles annealed at 700 °C and the emission intensities of the Eu3+ ions in the nanoparticles are mainly decided by the surface Eu3+ ions, the concentration of which decreases with increasing temperature. Incorporation of the nanoparticles in a poly(methyl methacrylate) (PMMA) matrix leads to a decrease in the 5D0 lifetime and this has been attributed to the quenching of the excited states of surface Eu3+ ions through the vibrations of different structural units in PMMA.
Total Synthesis of a 6,6‐Spiroketal Metabolite, Dinemasone A
Authors: Raji Reddy Chada , Srikanth Boinapally , Dilipkumar Uredi , Rao Kakita Veera Mohana , Jagadeesh Bharatam
Published: November 2012

The stereoselective total synthesis of dinemasone A has been accomplished. The key reactions, Sharpless asymmetric epoxidation, lithium‐mediated epoxy alcohol opening, and double‐intramolecular hetero‐Michael addition, gave access to dinemasone A from lactic acid esters. The stereochemistry at the spiro carbon was determined using extensive NMR studies.
Enhanced Electrocatalytic Reduction of Oxadiargyl and Its Determination on 2‐(4‐((4‐Acetylphenyl)diazenyl)phenylamino)‐ethanol Modified Graphene‐Paste Electrode
Authors: Saber‐Tehrani M. , Pourhabib A. , Husain S. Waqif , Arvand M.
Published: November 2012

The electrochemical behavior of oxadiargyl at a graphene‐paste electrode modified with an azo dye, 2‐(4‐((4‐acetylphenyl)diazenyl)phenylamino)ethanol (ADPE), ADPE/MGRPE was investigated. The modified electrode showed high electrocatalytic activity toward oxadiargyl. The apparent electron transfer rate constant (ks) and charge transfer coefficient (α) between electrode and ADPE were 1.16 s−1 and 0.41, respectively. The differential pulse voltammetry response of the modified graphene‐paste electrode was linear against the concentration of oxadiargyl in the range from 0.03 to 1.4 mg L−1. The limit of detection was found to be 1.3 µg L−1 (S/N=3). The practical analytical utility of this electrode was demonstrated by measurement of oxadiargyl in river water, soil and rice samples.
Automated AC Voltammetric Sensor for Early Fault Detection and Diagnosis in Monitoring of Electroplating Processes
Authors: Jaworski Aleksander , Wikiel Hanna , Wikiel Kazimierz
Published: November 2012

An in situ sensor employing AC‐voltammetry techniques was designed to provide a response strongly affected by the presence of specific disturbances like foreign contaminants, accumulated degradation products, severely out‐of‐target concentrations of electroplating bath constituents and out‐of‐target physical conditions of the plating process (i.e. temperature). Soft Independent Modelling of Class Analogy (SIMCA) is a pattern recognition method which describes each class separately in eigenvector space. In this supervised classification technique the projected new measurements are evaluated to determine whether they belong to a certain class or not. An automated analytical system was developed capable of collecting on‐line AC voltammetric data and investigating similarities between measurements in proper conditions and measurements with upset behavior with known disturbances which can be utilized to recognize a likely pattern of behavior. The shape differences between deformed and reference set voltammograms are quantified by Mahalanobis Distance (MD)‐SIMCA. In addition to the numerical approach, a graphical projection is utilized to diagnose the root cause of the detected process disturbances.
Amperometric Determination of Creatinine with a Dialysis Membrane‐Covered Nitrobenzene/Water Interface for Urine Analysis
Authors: Matsui Risa , Sakaki Toru , Osakai Toshiyuki
Published: November 2012

The ion transfer of creatinine (CRE) at a polarized nitrobenzene (NB)/water (W) interface has been studied. When the pH of the W phase is in the range of 1.2 to 4.0, a well‐defined voltammetric wave is observed for a simple transfer of CRE+ (protonated form) at the NB/W interface. This transfer reaction has been applied to develop an amperometric method for the determination of CRE in urine. In this system, the NB/W interface is covered with a dialysis membrane to prevent possible interference from urine proteins. The concentration of CRE in a urine control has successfully been determined.
The use of ballistic trajectory and granular flow models in predicting rockfall propagation
Authors: Bourrier Franck , Dorren Luuk , Hungr Oldrich
Published: November 2012

The term rockfall is often used ambiguously to describe various mass movement processes. Here we propose more precise terminology based on the physical nature of the moving mass, differentiating between two distinct types of rockfall: fragmental rockfall and rock mass fall. For both rockfall types, the current knowledge of the mechanisms controlling propagation of the mass movement are described, showing how these mechanisms can be simulated with different modelling approaches. However, we point out that almost no development has been realized concerning dynamic behaviour of the transitional processes between these two end‐member rockfall types. Some simplified means of dealing with these complications are suggested, but we emphasize that a considerable amount of fundamental methodological development remains necessary. Copyright © 2012 John Wiley & Sons, Ltd.
Simulated slope development sequences in a three‐dimensional context
Authors: Armstrong Adrian C.
Published: November 2012

Downvalley sequences of slope profiles have been inferred to represent temporal sequences. Results from a simulation model are presented which demonstrate that for a slope system in dynamic equilibrium, the downvalley variation in form is best explained as a response to downvalley variation in basal conditions, and hence that in such an equilibrium system the direct substitution of time for space is not valid.
Biochar-mediated reductive transformation of nitro herbicides and explosives
Authors: Oh Seok-Young , Son Jong-Gil , Chiu Pei C.
Published: November 2012

Biochar, a subset of black carbon produced via pyrolysis of biomass, has received much attention in recent years due to its potential to address many important issues, from energy and climate to agriculture and environmental quality. Biochar is known to influence the fate and transport of organic contaminants, although its role has been generally assumed to be as an adsorbent. In this study, the authors investigated the ability of biochar to catalyze the reductive reactions of nitro herbicides and explosives. Two biochars, derived from poultry litter and wastewater biosolids, were found to promote the reductive removal of the dinitro herbicides pendimethalin and trifluralin and the explosives 2,4-dinitrotoluene and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by dithiothreitol. Parallel experiments using another black carbon material, graphite powder or granular activated carbon, in place of a biochar resulted in comparable rate enhancement to show reduction products, such as 2,4-diaminotoluene and formaldehyde. A cyclization product of trifluralin and reduction products of dinitrotoluene and RDX were detected only when biochar and dithiothreitol were both present, supporting the ability of biochar to promote redox reactions. Three possible catalysts, including graphene moieties, surface functional groups, and redox-active metals, in biochar may be responsible for the biochar-mediated reactions. The environmental significance, implications, and applications of this previously unrecognized role of biochar are discussed. Environ. Toxicol. Chem. 2013;32:501–508. © 2012 SETAC
On a relaxation method for mathematical programs with vanishing constraints
Authors: Achtziger Wolfgang , Kanzow Christian , Hoheisel Tim
Published: November 2012

The paper considers a numerical approach for the solution of mathematical problems with vanishing constraints (MPVC). It is well known that direct numerical approaches for the treatment of MPVCs typically fail because standard constraint qualifications usually are not satisfied at a local minimizer. This parallels the situation in the related class of mathematical programs with equilibrium constraints (MPEC). For MPVC several concepts of stationarity have been proposed in the last few years generalizing the usual KKT‐conditions. The paper considers a direct relaxation approach where the original problem is replaced by a perturbed problem. This approach has also been investigated by Izmailov and Solodov [1]. Under standard regularity conditions, we prove the convergence of KKT‐points of the perturbed problem to suitable stationary points of the MPVC. Moreover, conditions are provided showing convergence to a strongly stationary point (i.e., a KKT‐point) of MPVC. The paper closes with a numerical test of this approach for a problem arising in the field of topology optimization of mechanical structures with vanishing stress constraints (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Existence and uniqueness of a global weak solution of a Darcy‐Nernst‐Planck‐Poisson system
Authors: Herz Matthias , Ray Nadja , Knabner Peter
Published: November 2012

This paper deals with the analytical investigations of a nonstationary Darcy‐Nernst‐Planck‐Poisson‐type system which is a mathematical model describing electrolyte solutions. For this nonlinear fully coupled system of partial differential equations we proof existence and uniqueness of global weak solutions. Furthermore, we establish physical properties for the number densities such as nonnegativity and boundedness in L∞((0, T) × Ω) (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis and Properties of Thieno[3,2‐b]thiophene Derivatives for Application of OFET Active Layer
Authors: Ito Hiroki , Yamamoto Tatsuya , Yoshimoto Noriyuki , Tsushima Noboru , Muraoka Hiroki , Ogawa Satoshi
Published: November 2012

A series of thieno[3,2‐b]thiophene derivatives having styryl groups were synthesized via short steps and characterized by UV–vis absorption spectra and cyclic voltammetry. Based on these results, we found that the introduction of long chain alkyl groups to the terminal styryl groups leads to narrower HOMO–LUMO gaps and higher HOMO energy levels than the unalkylated styryl substituted molecules. Organic field–effect transistor (OFET) devices using these derivatives as the active layer were fabricated by a vacuum deposition process. It was demonstrated that these devices showed a relatively high hole mobility up to 3.5 × 10−2 cm2/Vs. These devices also showed a good stability, namely their mobilities did not decrease over 100 days in air. Therefore, these facts suggested that the introduction of long‐chain alkylated styryl groups is an effective way to improve the hole mobilities in OFETs. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 24:25–35, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.21059
INFORMAL PAYMENTS AND HEALTH WORKER EFFORT: A QUANTITATIVE STUDY FROM TANZANIA
Authors: Lindkvist Ida
Published: November 2012

Informal payments—payments made from patients to health personnel in excess of official fees—are widespread in low‐income countries. It is not obvious how such payments affect health worker effort. On the one hand, one could argue that because informal payments resemble formal pay for performance schemes, they will incite higher effort in the health sector. On the other hand, health personnel may strategically adjust their base effort downwards to maximise patients' willingness to pay informally for extra services. To explore the relationship between informal payments and health worker effort, we use a unique data set from Tanzania with over 2000 observations on the performance of 156 health workers. Patient data on informal payments are used to assess the likelihood that a particular health worker accepts informal payment. We find that health workers who likely accept payments do not exert higher average effort. They do however have a higher variability in the effort they exert to different patients. These health workers are also less sensitive to the medical condition of the patient. A likely explanation for these findings is that health workers engage in rent seeking and lower baseline effort to induce patients to pay. Copyright © 2012 John Wiley & Sons, Ltd.
Low‐Rac1 activity downregulates MC3T3‐E1 osteoblastic cell motility on a nanoscale topography prepared on polystyrene substrates in vitro
Authors: Zheng Liling , Kim Hyun‐Man
Published: November 2012

Surface roughness affects various cell activities, including osteoblast motility, which may have an effect on bone regeneration. Defective cell signaling, which is associated with the slow motility of osteoblasts on a substrate with rough topology at nanometer dimensions (Ra = 123.8 ± 29.1 nm), was studied. Osteoblasts grown on the rough surface at nanometer dimensions showed the high activities of small GTPase RhoA and Rho‐associated kinase (ROCK) on the rough surface at nanometer dimensions and downregulated Rac1 activity compared to the smooth surface. The inhibition of ROCK in the cells with Y‐27632, a specific ROCK inhibitor, reversed the low‐cell motility. In addition, the transfection of constitutively active Rac1 reversed the low‐cell motility. However, Rac1 inhibition abolished the reversal of low‐cell motility induced by ROCK inhibition. These results indicate that upregulated RhoA/ROCK activity suppresses Rac1 activity to decrease the motility of osteoblasts on a rough surface at nanometer dimensions, and the low motility of osteoblasts on a rough surface at nanometer dimensions can be reversed by ROCK inhibition. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Self‐assembly of model graft copolymers of agarose and weak polyelectrolyte‐based amphiphilic diblock copolymers: Controlled drug release and degradation
Authors: Muppalla Ravikumar , Jewrajka Suresh K. , Prasad Kamalesh
Published: November 2012

Polysaccharide‐based copolymers are promising biomaterials due to their biocompatibility and biodegradability. For potential biomedical applications the copolymer as a whole and all the degraded species must be biocompatible and easily removable from the system. In this regards, new model pH‐responsive seaweed agarose (Agr) grafted with weak polyelectrolyte‐based well‐defined amphiphilic block copolymers ca. poly[(methyl methacrylate)‐b‐(2‐dimethylamino)ethyl methacrylate)] (PMMA‐b‐PDMA) were designed and synthesized to study the self‐assembly, degradation, and in vitro hydrophobic/hydrophilic drug release behavior. The graft copolymer solutions display extremely low critical micelle concentration (CMC) and form pH responsive stable micelles. The degradation study of the graft copolymer reveals that the entire degraded components are well soluble/dispersible in water due to formation of mixed micelles. The micelles are also strongly adsorbed on the mica surface owing to electrostatic interaction. One application of the graft copolymer micelles is that it can entrap both hydrophilic and poorly water soluble hydrophobic drugs effectively and exhibit slow release kinetics. The release kinetics of both the hydrophilic and poorly water soluble hydrophobic drugs change with pH as well as with the composition of the graft copolymer. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: , 2013.
Efficacy of mesoporous silica nanoparticles in delivering BMP‐2 plasmid DNA for in vitro osteogenic stimulation of mesenchymal stem cells
Authors: Kim Tae‐Hyun , Kim Meeju , Eltohamy Mohamed , Yun Ye‐Rang , Jang Jun‐Hyeog , Kim Hae‐Won
Published: November 2012

We report the ability of aminated mesoporous silica nanoparticles (MSN–NH2) with large mesopore space and positive‐charged surface to deliver genes within rat mesenchymal stem cells (MSCs). The amine functionalized inorganic nanoparticles were complexed with bone morphogenetic protein‐2 (BMP2) plasmid DNA (pDNA) to study their transfection efficiency in MSCs. Intracellular uptake of the complex BMP2 pDNA/MSN–NH2 occurred significantly, with a transfection efficiency of approximately 68%. Furthermore, over 66% of the transfected cells produced BMP2 protein. The osteogenic differentiation of the transfected MSCs was demonstrated by the expression of bone‐related genes and proteins including bone sialoprotein, osteopontin, and osteocalcin. The MSN–NH2 delivery vehicle for BMP2 pDNA developed in this study may be a potential gene delivery system for bone tissue regeneration. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Part II: Enhancement of transcorneal delivery of gatifloxacin by solid lipid nanoparticles in comparison to commercial aqueous eye drops
Authors: Abul Kalam Mohd. , Sultana Yasmin , Ali Asgar , Aqil Mohd. , Mishra Anil K. , Chuttani Krishna , Aljuffali Ibrahim A. , Alshamsan Aws
Published: November 2012

This study describes corneal permeation of gatifloxacin from solid lipid nanoparticle (SLN) through the cornea and its effect on corneal hydration level. The aqueous humor levels of gatifloxacin after single topical instillation in Gate® Eyedrops and positively charged SLN‐C were determined. A 3.37‐fold increase in the relative bioavailability was observed with the SLN‐C (AUC0→∞ 2.192 μg mL−1 h) (AUC, area under the curve) as compared to Gate® Eyedrops (AUC0→∞ 0.651 μg mL−1 h). The t1/2 of drug in SLN‐C exhibited a 2.34‐fold higher than Gate® Eyedrops seem to be significantly increased (p > 0.05), Cmax of gatifloxacin from SLN‐C showed 1.09‐fold higher concentration as compared to Gate® Eyedrops. The results suggested that SLNs could enhance ocular bioavailability of gatifloxacin and prolong its residence time in the eyes. Moreover, no signs of ocular irritation were seen with the SLN formulations, indicating their relative safety compared to the marketed drops. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
In vitro and in vivo studies on nanocrystalline Ti fabricated by equal channel angular pressing with microcrystalline CP Ti as control
Authors: Nie F. L. , Zheng Y. F. , Wei S.C. , Wang D. S. , Yu Z. T. , Salimgareeva G. K. , Polyakov A. V. , Valiev R. Z.
Published: November 2012

Bulk nanocrystalline Ti bars (Grade 4, ϕ4 × 3000 mm3) were massively fabricated by equal channel angular pressing (ECAP) via follow‐up conform scheme with the microcrystalline CP Ti as raw material. Homogeneous nanostructured crystals with the average grain size of 250 nm were identified for the ECAPed Ti, with extremely high tensile/fatigue strength (around 1240/620 MPa) and adorable elongation (more than 5%). Pronounced formation of bonelike apatite for the nanocrystalline Ti group after 14 days static immersion in simulated body fluids (SBF) reveals the prospective in vitro bioactive capability of fast calcification, whereas an estimated 17% increment in protein adsorption represents good bioaffinity of nanocrystalline Ti. The documentation onto the whole life circle of osteoblast cell lines (MG63) revealed the strong interactions and superior cellular functionalization when they are co‐incubated with bulk nanocrystalline Ti sample. Moreover, thread‐structured specimens were designed and implanted into the tibia of Beagles dogs till 12 weeks to study the in vivo responses between bone and metallic implant made of bulk nanocrystalline Ti, with the microcrystalline Ti as control. For the implanted nanostructured Ti group, neoformed bone around the implants underwent the whole‐stage transformation proceeding from originally osteons or immature woven bone to mature lamellar bone (skeletonic trabecular), even with the remodeling being finished till 12 weeks. The phenomenal osseointegration of direct implant‐bone contact can be revealed from the group of the ECAPed Ti without fibrous tissue encapsulation in the gap between the implant and autogenous bone. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Enzymatic modification of regenerated cellulosic fabrics to improve bacteria sorption properties
Authors: Akbari M. , Dadadashian F. , Kordestani S. S. , Xue M. , Jackson C. J.
Published: November 2012

This research investigates the effect of enzymatic treatment of two different regenerated cellulosic fibers (Lyocell and viscose) on their ability of bacteria sorption from an aqueous suspension. The sorption of Escherichia coli (E. coli, Gram negative) and Staphylococcus aureus (S. aureus, Gram positive) cells by treated Lyocell and viscose fabrics were determined by measuring the optical density (OD) of the remaining bacteria suspension after removal of the fabric samples using spectrometry. Fourier transform infrared spectroscopy and scanning electron microscopy (SEM) were utilized to investigate structural and morphological changes of the enzyme treated samples. The result showed that the moisture content and crystallinity of both viscose and Lyocell samples increased after enzymatic treatment. Comparing the results of OD measurements indicated that enzymatic treatment of cellulosic samples significantly increased the bacteria absorption properties compared to those untreated samples. However, treated samples showed different ranges of sorption ability with different kinds of bacteria. The maximum bacteria sorption of 38% and 37% of E. coli bacteria from an aqueous suspension was found for the treated viscose and Lyocell samples compared with only 20% and 10% of the untreated viscose and Lyocell samples, respectively. It was also found that S. aureus sorption of cellulose‐treated viscose and Lyocell fabrics from a bacterial suspension could significantly improve up to 33% compared with only 5% of untreated samples. Furthermore, SEM micrographs confirmed that bacterial sorption of the cellulose‐treated samples were effectively improved in terms of their uniform sorption on the fibers surface. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Nanopatterning effects on astrocyte reactivity
Authors: Ereifej Evon S. , Matthew Howard W. , Newaz Golam , Mukhopadhyay Ashis , Auner Gregory , Salakhutdinov Ildar , VandeVord Pamela J.
Published: November 2012

An array of design strategies have been targeted toward minimizing failure of implanted microelectrodes by minimizing the chronic glial scar around the microelectrode under chronic conditions. Current approaches toward inhibiting the initiation of glial scarring range from altering the geometry, roughness, size, shape, and materials of the device. Studies have shown materials which mimic the nanotopography of the natural environment in vivo will consequently result in an improved biocompatible response. Nanofabrication of electrode arrays is being pursued in the field of neuronal electrophysiology to increase sampling capabilities. Literature shows a gap in research of nanotopography influence in the reduction of astrogliosis. The aim of this study was to determine optimal feature sizes for neural electrode fabrication, which was defined as eliciting a nonreactive astrocytic response. Nanopatterned surfaces were fabricated with nanoimprint lithography on poly(methyl methacrylate) surfaces. The rate of protein adsorption, quantity of protein adsorption, cell alignment, morphology, adhesion, proliferation, viability, and gene expression was compared between nanopatterned surfaces of different dimensions and non‐nanopatterned control surfaces. Results of this study revealed that 3600 nanopatterned surfaces elicited less of a response when compared with the other patterned and non‐nanopatterned surfaces. The surface instigated cell alignment along the nanopattern, less protein adsorption, less cell adhesion, proliferation and viability, inhibition of glial fibrillary acidic protein, and mitogen‐activated protein kinase kinase 1 compared with all other substrates tested. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Degree of biological apatite c-axis orientation rather than bone mineral density controls mechanical function in bone regenerated using recombinant bone morphogenetic protein-2
Authors: Ishimoto Takuya , Nakano Takayoshi , Umakoshi Yukichi , Yamamoto Masaya , Tabata Yasuhiko
Published: November 2012

The aim of the present study was to assess the bone regeneration process in defects introduced into rabbit long bones, which were regenerated with controlled release of recombinant bone morphogenetic protein-2 (rBMP-2). The orientation of the biological apatite (BAp) c-axis and bone mineral density (BMD) were compared as predictors of bone mechanical function. A 20-mm-long defect was introduced in rabbit ulnas, and 17 µg of rBMP-2 was controlled-released into the defect using a biodegradable gelatin hydrogel as the carrier. In the bone regeneration process, two characteristic phases may have been governed by different factors. First, new bone formation actively occurred, filling the bone defect with newly formed bone tissue and increasing the BMD. This process was regulated by the strong osteoinductive capacity of rBMP-2. Second, after filling of the defect and moderate BMD restoration, preferential BAp c-axis orientation began to increase, coincident with initiation of remodeling. In addition, the BAp c-axis orientation, rather than BMD, was strongly correlated with Young's modulus, an important index of bone mechanical function, particularly in the later stage of bone regeneration. Thus, preferential BAp c-axis orientation is a strong determinant and predictor of the mechanical function of tissue-engineered bone. Therefore, analysis of BAp preferential c-axis orientation in addition to measurement of BMD is crucial in assessment of bone mechanical function. © 2013 American Society for Bone and Mineral Research © 2013 American Society for Bone and Mineral Research
High physical fitness in young adulthood reduces the risk of fractures later in life in men: A nationwide cohort study
Authors: Nordström Peter , Sievänen Harri , Gustafson Yngve , Pedersen Nancy L , Nordström Anna
Published: November 2012

A few studies have indicated that self-reported physical activity is associated with the risk of fractures in middle-aged and elderly men. We investigated whether objectively measured physical fitness in young adulthood was associated with the risk of low-energy fractures later in life in men. Aerobic capacity and isometric muscle strength were measured in 435,445 Swedish men who were conscripted for military service from 1969 to 1978. Incident fractures were searched in national registers. During a median follow-up period of 35 years (range, 11–41 years), 8030 subjects sustained at least one fracture, increasing the risk of death 1.8 times (95% CI, 1.6–2.0) during follow up. When comparing men in the lowest and highest decile of physical fitness, the risk of a fracture was 1.8 times higher (95% CI, 1.6–2.1) and that of hip fracture was 2.7 times higher (95% CI, 1.6–4.7). The risk of fracture was also 1.4 to 1.5 times higher when comparing the extreme deciles of muscle strength (p < 0.001 for all). In a subcohort of 1009 twin pairs, up to 22% of the variation in physical fitness and 27% to 39% of the variation in muscle strength was attributable to environmental factors unique to one twin; eg, physical activity. In conclusion, low aerobic capacity and muscle strength in young adulthood are associated with an increased risk of low-energy fractures later in life. © 2013 American Society for Bone and Mineral Research.
β-catenin promotes bone formation and suppresses bone resorption in postnatal growing mice
Authors: Chen Jianquan , Long Fanxin
Published: November 2012

Genetic studies in the mouse have demonstrated multiple roles for β-catenin in the skeleton. In the embryo, β-catenin is critical for the early stages of osteoblast differentiation. Postnatally, β-catenin in mature osteoblasts and osteocytes indirectly suppresses osteoclast differentiation. However, a direct role for β-catenin in regulating osteoblast number and/or function specifically in the postnatal life has not been demonstrated. Addressing this knowledge gap is important because low-density lipoprotein receptor-related protein 5 (LRP5), a coreceptor for WNT signaling proposed to function through β-catenin, controls osteoblast number and function in postnatal mice or humans. To overcome the neonatal lethality caused by embryonic deletion of β-catenin in early-stage osteoblast-lineage cells, we use the Osx-CreERT2 mouse strain to remove β-catenin in Osterix (Osx)-expressing cells by administering tamoxifen (TM) temporarily to postnatal mice. Lineage-tracing experiments in the long bones demonstrate that Osx-CreERT2 targets predominantly osteoblast-lineage cells on the bone surface, but also transient progenitors that contribute to bone marrow stromal cells and adipocytes. Deletion of β-catenin by this strategy greatly reduces the bone formation activity of the targeted osteoblasts. However, the targeted osteoblasts rapidly turn over and are replaced by an excessive number of non-targeted osteoblasts, causing an unexpected increase in bone formation, but an even greater increase in osteoclast number and activity produces a net effect of severe osteopenia. With time, the mutant mice also exhibit a marked increase in bone marrow adiposity. Thus, β-catenin in postnatal Osx-lineage cells critically regulates bone homeostasis by promoting osteoblast activity and suppressing osteoblast turnover, while restraining osteoclast and marrow fat formation. © 2013 American Society for Bone and Mineral Research.