bluuebunny/crossref_metadata_2025 huggingface dataset:
The Impact of Neural Stem Cell Biology on CNS Carcinogenesis and Tumor Types
Authors: Kurian K. M.
Published: May 2011

The incidence of gliomas is on the increase, according to epidemiological data. This increase is a conundrum because the brain is in a privileged protected site behind the blood-brain barrier, and therefore partially buffered from environmental factors. In addition the brain also has a very low proliferative potential compared with other parts of the body. Recent advances in neural stem cell biology have impacted on our understanding of CNS carcinogenesis and tumor types. This article considers the cancer stem cell theory with regard to CNS cancers, whether CNS tumors arise from human neural stem cells and whether glioma stem cells can be reprogrammed.
Intracellular APP Domain Regulates Serine‐Palmitoyl‐CoA Transferase Expression and Is Affected in Alzheimer′s Disease
Authors: Grimm Marcus O. W. , Grösgen Sven , Rothhaar Tatjana L. , Burg Verena K. , Hundsdörfer Benjamin , Haupenthal Viola J. , Friess Petra , Müller Ulrike , Fassbender Klaus , Riemenschneider Matthias , Grimm Heike S. , Hartmann Tobias
Published: May 2011

Lipids play an important role as risk or protective factors in Alzheimer′s disease (AD), a disease biochemically characterized by the accumulation of amyloid beta peptides (Aβ), released by proteolytic processing of the amyloid precursor protein (APP). Changes in sphingolipid metabolism have been associated to the development of AD. The key enzyme in sphingolipid de novo synthesis is serine‐palmitoyl‐CoA transferase (SPT). In the present study we identified a new physiological function of APP in sphingolipid synthesis. The APP intracellular domain (AICD) was found to decrease the expression of the SPT subunit SPTLC2, the catalytic subunit of the SPT heterodimer, resulting in that decreased SPT activity. AICD function was dependent on Fe65 and SPTLC2 levels are increased in APP knock‐in mice missing a functional AICD domain. SPTLC2 levels are also increased in familial and sporadic AD postmortem brains, suggesting that SPT is involved in AD pathology.
Validation of a Diagnostic Microarray for Human Papillomavirus: Coverage of 102 Genotypes
Authors: Arron Sarah Tuttleton , Skewes-Cox Peter , Do Phong H. , Dybbro Eric , Da Costa Maria , Palefsky Joel M. , DeRisi Joseph L.
Published: May 2011

Papillomaviruses have been implicated in a variety of human diseases ranging from common warts to invasive carcinoma of the anogenital mucosa. Existing assays for genotyping human papillomavirus are restricted to a small number of types. Here, we present a comprehensive, accurate microarray strategy for detection and genotyping of 102 human papillomavirus types and validate its use in a panel of 91 anal swabs. This array has equal performance to traditional dot blot analysis with the benefits of added genotype coverage and the ability to calibrate readout over a range of sensitivity or specificity values.
Bendamustine: Safety and Efficacy in the Management of Indolent Non-Hodgkins Lymphoma
Authors: Tageja Nishant
Published: May 2011

Bendamustine (Treanda, Ribomustin) was recently approved by the US Food and Drug Administration (FDA) for treatment of patients with rituximab refractory indolent lymphoma and is expected to turn into a frontline therapy option for indolent lymphoma. This compound with amphoteric properties was designed in the former Germany Democratic Republic in 1960s and re-discovered in 1990s with multiple successive well-designed studies. Bendamustine possesses a unique mechanism of action with potential antimetabolite properties, and only partial cross-resistance with other alkylators. Used in combination with rituximab in vitro, bendamustine shows synergistic effects against various leukemia and lymphoma cell lines. In clinical studies, bendamustine plus rituximab is highly effective in patients with relapsed-refractory indolent lymphoma, inducing remissions in 90% or more and a median progression-free survival of 23–24 months. The optimal dosing and schedule of bendamustine administration is largely undecided and varies among studies. Results of ongoing trials and dose-finding studies will help to further help ascertain the optimal place of bendamustine in the management of indolent NHL.
Avatars Go to Class: A Virtual Environment Soil Science Activity
Authors: Mamo M. , Namuth‐Covert D. , Guru A. , Nugent G. , Phillips L. , Sandall L. , Kettler T. , McCallister D.
Published: May 2011

Web 2.0 technology is expanding rapidly from social and gaming uses into the educational applications. Specifically, the multi‐user virtual environment (MUVE), such as SecondLife, allows educators to fill the gap of first‐hand experience by creating simulated realistic evolving problems/games. In a pilot study, a team of educators at the University of Nebraska‐Lincoln and eXtension created a soil and water environmental case study using SecondLife in eXtension's Morrill2 Island for testing and use by students in an introductory soil science course (n = 126). In this pilot test with a class period of 110 minutes, approximately half of the students (n = 64) were first given an orientation on how to navigate in SecondLife before beginning the soil and water pollution activity. Another group of students (n = 62) formed a control group and completed the same activity using a traditional paper and pencil method and using supporting data presented in table or graphics format. A pre‐activity survey suggested that about 33% of all students had some level of experience with virtual environments and/or playing computer/video games. Results from a randomized experiment showed that the average post‐test score for the control group was 8.38 (out of a possible 12 points), which was significantly higher than the 7.34 for the SecondLife group. Post‐activity student survey results suggested that students prefer to have educationally designed virtual interactive objects such as simulation activities and experiments, characters with whom to interact and gain information, and overall more action and gaming features to benefit their educational experience. While SecondLife and other simulation software packages have potential for educational use, in order to improve learning, the design of the activity within the technology must be pedagogically sound and also create tasks that capture and engage the learner.
Quaternary Glacial Mapping in Western Wisconsin Using Soil Survey Information
Authors: Oehlke Betsy M. , Dolliver Holly A. S.
Published: May 2011

The majority of soils in the western Wisconsin have developed from glacial sediments deposited during the Quaternary Period (2.6 million years before present). In many regions, multiple advances and retreats have left a complex landscape of diverse glacial sediments and landforms. The soils that have developed on these deposits reflect the nature of the parent material and glacial sediments. Data from the Soil Survey Geographic (SSURGO) database were utilized to digitally map Quaternary deposits and in St. Croix County, Wisconsin. Maps of ice source region (northwest vs. northeast) and parent materials (till vs. outwash) were produced. Results were compared to a preliminary Quaternary surficial geology map. Overall agreement between the geologic map and the map created using soil survey information was generally greater than 60%. This research shows that soil surveys can provide reliable, accurate, and high‐resolution data on Quaternary surficial geology. In addition, this research shows the linkage and value of soil science to other disciplines such as geology.
Aerosol hygroscopicity and CCN activation kinetics in a boreal forest environment during the 2007 EUCAARI campaign
Authors: Cerully K. M. , Raatikainen T. , Lance S. , Tkacik D. , Tiitta P. , Petäjä T. , Ehn M. , Kulmala M. , Worsnop D. R. , Laaksonen A. , Smith J. N. , Nenes A.
Published: May 2011

Abstract. Measurements of size-resolved cloud condensation nuclei (CCN), subsaturated hygroscopic growth, size distribution, and chemical composition were collected from March through May, 2007, in the remote Boreal forests of Hyytiälä, Finland, as part of the European Integrated project on Aerosol Cloud Climate and Air Quality Interactions (EUCAARI) campaign. Hygroscopicity parameter, κ, distributions were derived independently from Continuous Flow-Streamwise Thermal Gradient CCN Chamber (CFSTGC) and Hygroscopicity Tandem Differential Mobility Analyzer (HTDMA) measurements. CFSTGC-derived κ values for 40, 60, and 80 nm particles range mostly between 0.10 and 0.40 with an average of 0.20 ± 0.10; this is characteristic of highly oxidized organics and reflect their dominant influence in this environment. HTDMA-derived κ were generally 30 % lower. Diurnal trends of κ show a minimum at sunrise and a maximum in the late afternoon; this trend covaries with inorganic mass fraction and the m/z 44 organic mass fraction given by a quadrupole aerosol mass spectrometer, further illustrating the importance of ageing on aerosol hygroscopicity. The chemical dispersion inferred from the observed κ distributions indicates that while 60 and 80 nm dispersion increases around midday, 40 nm dispersion remains constant. Additionally, 80 nm particles show a markedly higher level of chemical dispersion than both 40 and 60 nm particles. An analysis of droplet activation kinetics for the sizes considered indicates that the CCN activate as rapidly as (NH4)2SO4 calibration aerosol.
Retrieval of temperature and pressure using broadband solar occultation: SOFIE approach and results
Authors: Marshall B. T. , Deaver L. E. , Thompson R. E. , Gordley L. L. , McHugh M. J. , Hervig M. E. , Russell III J. M.
Published: May 2011

Abstract. Measurement of atmospheric temperature as a function of pressure, T(P), is key to understanding many atmospheric processes and a prerequisite for retrieving gas mixing ratios and other parameters from solar occultation measurements. This paper gives a brief overview of the solar occultation measurement technique followed by a detailed discussion of the mechanisms that make the measurement sensitive to temperature. Methods for retrieving T(P) using both broadband transmittance and refraction are discussed. Investigations using measurements of broadband transmittance in two CO2 absorption bands (the 4.3 and 2.7 μm bands) and refractive bending are then presented. These investigations include sensitivity studies, simulated retrieval studies, and examples from SOFIE.
Observations and modelling of 1/f-noise in weather and climate
Authors: Blender R. , Zhu X. , Fraedrich K.
Published: May 2011

Abstract. Data with power spectra close to S(f)~1/f is denoted as 1/f or flicker noise. High resolution measurements during TOGA/COARE for temperature, humidity, and wind speed (1\\,min resolution) reveal 1/f spectra while precipitation shows no power-law scaling during the same period. However, a binary time series indicating the precipitation events (1 for precipitation, 0 for no precipitation) shows a clear 1/f spectrum in line with the remaining boundary layer data. For extreme events in time series with 1/f spectra the return time distribution is well approximated by a Weibull-distribution for short and long return times. The daily discharge of the Yangtze river shows high volatility which is linked to the intra-annual 1/f spectrum. The discharge fluctuations detected in different time windows are represented by a single function (a so-called data collapse) similar to the universal behavior found for turbulence and various physical systems at criticality. The collapse is well described by the Gumbel distribution.
Point observations of liquid water content in wet snow – investigating methodical, spatial and temporal aspects
Authors: Techel F. , Pielmeier C.
Published: May 2011

Abstract. Information about the volume and the spatial and temporal distribution of liquid water in snow is important for forecasting wet snow avalanches and for predicting melt-water run-off. The distribution of liquid water in snow is commonly estimated from point measurements using a "hand" squeeze test, or a dielectric device such as a "Snow Fork" or a "Denoth meter". Here we compare estimates of water content in the Swiss Alps made using the hand test to those made with a Snow Fork and a Denoth meter. Measurements were conducted in the Swiss Alps, mostly above tree line; more than 12 000 measurements were made at 85 locations over 30 days. Results show that the hand test generally over estimates the volumetric liquid water content. Estimates using the Snow Fork are generally 1 % higher than those derived from the Denoth meter. The measurements were also used to investigate temporal and small-scale spatial patterns of wetness. Results show that typically a single point measurement does not characterize the wetness of the surrounding snow. Large diurnal changes in wetness are common in the near-surface snow, and associated changes at depth were also observed. A single vertical profile of measurements is not sufficient to determine whether these changes were a result of a spatially homogeneous wetting front or caused by infiltration through pipes. Based on our observations, we suggest that three measurements at horizontal distances greater than 50 cm are needed to adequately characterize the distribution of liquid water through a snowpack. Further, we suggest a simplified classification scheme that includes five wetness patterns that incorporate both the vertical and horizontal distribution of liquid water in a snowpack.
Advances in Robust Parameter Design: From Taguchi's Inner‐Outer Arrays to Combined Arrays
Authors: Evangelaras Haralambos , Koukouvinos Christos , Koutras Markos V.
Published: May 2011

Robust parameter design, originally proposed by Taguchi, is an off‐line technique for maintaining variance reduction and improving quality. According to Taguchi, product variation from the desirable target is affected by two types of factors: control factors and noise factors. The basic idea in robust parameter design is to identify the levels of the control factors so that the product's quality characteristic becomes insensitive to changes in the levels of the noise factors. As a consequence, the effect of uncontrollable variations on the response will be reduced.

Taguchi suggested the use of inner‐outer arrays with the control factors being assigned to an inner array and the noise factors assigned to an outer array. After the collection of the data, a performance measure called signal‐to‐noise ratio is calculated and analyzed in order to identify the optimal levels of the control factors. After the introduction of Taguchi's philosophy in the field of experimental design and data analysis, several new designs and techniques have been explored and adopted in this field. This chapter overviews well established approaches and analysis techniques that have been exploited to the robust parameter design field.
Applicability of Statistics and Probability Theory to Nucleate Pool Boiling Heat Transfer
Authors: Judd R.L. , Balakrishnan N.
Published: May 2011

Much has been learned about nucleate pool boiling over the last sixty years through experimental investigation and recently, it has become possible to predict the relationships governing the nucleation, growth and departure or collapse of bubbles computationally. However, it has not been possible to develop a theory capable of predicting the rate of heat transfer because of the inability to incorporate surface conditions in a comprehensive boiling heat transfer model. A method is proposed to simulate the surface conditions through the interactions of a large population of potentially active nucleation sites and a much smaller population of dominant nucleation sites using Monte Carlo simulation.
Fluorescence‐based fouling prediction and optimization of a membrane filtration process for drinking water treatment
Authors: Peiris Ramila H. , Budman Hector , Moresoli Christine , Legge Raymond L.
Published: May 2011

A novel fluorescence‐based approach is proposed for modeling, predicting, and optimizing different fouling dynamics in an ultrafiltration (UF) process for drinking water treatment. Principal component analysis (PCA) was used to extract information in terms of principal components (PCs), related to major membrane foulant groups, from fluorescence excitation–emission matrix measurements captured during UF of natural river water. The evolution of PC scores during the filtration process was then related to membrane fouling using dynamic balances of latent variable values (PC scores). This approach was found suitable for forecasting fouling behaviors with good accuracy based solely on fluorescence data collected 15 min from the start of the filtration. The proposed approach was tested experimentally through model‐based optimization of backwashing times with the objective of minimizing the energy consumption per unit amount of water produced during the filtration process. This approach was also useful for identifying fouling groups contributing to reversible and irreversible fouling. © 2011 American Institute of Chemical Engineers AIChE J, 2012
Myelodysplastic syndromes: 2011 update on diagnosis, risk‐stratification, and management
Authors: Garcia‐Manero Guillermo
Published: May 2011

Disease overview:

The myelodysplastic (MDS) are a very heterogeneous group of myeloid disorders characterized by peripheral blood cytopenias and increased risk of transformation to acute myelogenous leukemia (AML). MDS occurs more frequently in older male and in individuals with prior exposure to cytotoxic therapy.

Diagnosis:

Diagnosis of MDS is based on morphological evidence of dysplasia upon visual examination of a bone marrow aspirate and biopsy. Information obtained from additional studies such as karyotype, flow cytometry, or molecular genetics is complementary but not diagnostic.

Risk‐stratification:

Prognosis of patients with MDS can be calculated using a number of scoring systems. In general, all these scoring systems include analysis of peripheral cytopenias, percentage of blasts in the bone marrow, and cytogenetic characteristics. The most commonly used system is the International Prognostic Scoring System. This score divides patients into a lower risk subset (low and intermediate‐1) and a higher risk subset (int‐2 and high). Other more modern systems have been developed that allow more precise risk calculation.

Risk‐adapted therapy:

Therapy is selected based on risk, transfusion needs, percent of bone marrow blasts and more recently cytogenetic profile. Goals of therapy are different in lower risk patients than in higher risk. In lower risk, the goal is to decrease transfusion needs and transformation to higher risk disease or AML. In higher risk, the goal is to prolong survival. Current available therapies include growth factor support, lenalidomide, hypomethylating agents, intensive chemotherapy, and allogeneic stem cell transplantation. The use of lenalidomide has significant clinical activity in patients with lower risk disease, anemia, and a chromosome 5 alteration. 5‐azacitidine and decitabine have activity in higher risk MDS. 5‐azacitidine has been shown to improve survival in higher risk MDS. Additional supportive care measures may include the use of prophylactic antibiotics and iron chelation.

Management of progressive or refractory disease:

At the present time, there are no approved interventions for patients with progressive or refractory disease particularly after hypomethylating based therapy. Options include cytarabine‐based therapy, transplantation, and participation on a clinical trial. Am. J. Hematol. 86:491–498, 2011. © 2011 Wiley‐Liss, Inc.
Infrared imaging for leak detection of N95 filtering facepiece respirators: A pilot study
Authors: Roberge Raymond J. , Monaghan William D. , Palmiero Andrew J. , Shaffer Ronald , Bergman Michael S.
Published: May 2011

Background

This study was undertaken to determine the utility of an infrared camera (IRC) for assessing leaks around filtering facepiece respirators (FFR) during quantitative respirator fit testing.

Methods

Eight subjects underwent quantitative fit testing on six N95 FFR models (48 total fit tests) while simultaneously being recorded with an IRC.

Results

The IRC detected 49 exhalation leaks during 39 tests and no leaks in nine tests. Exhalation leaks were identified in all failed fit tests (13) and a majority (26 of 35) of passed tests. Anatomically, the nasal region and malar (cheekbone) regions accounted for 71% of identified leak sites. Fit factors for fit tests without identified exhalation leaks were significantly higher than fit tests with leaks detected by IRC (P = 0.01).

Conclusions

Thermal imaging using IRC can detect leaks in respiratory protective equipment and has the potential as a screening tool for assessment of the adequacy of post‐donning FFR fit. Am. J. Ind. Med. 54:628–636, 2011. © 2011 Wiley‐Liss, Inc.
Ethnic disparities in the perception of ethical risks from psychiatric genetic studies
Authors: Nwulia E.A. , Hipolito M.M. , Aamir S. , Lawson W.B. , Nurnberger J.I. ,   BiGS,   Consortium
Published: May 2011

To examine if ethnic differences in concerns about unfavorable consequences from psychiatric genetic studies, existing between non‐Hispanic Black and White populations, persist among participants in an actual genetic study of bipolar disorder. Historically, minority subjects have been less willing to participate in such studies. Participants in the US Bipolar Genome Study (BIGS) were assessed on six items of concerns in the Questionnaire on Genetic Risk (QGR). Each item had five response categories, ranging from “not at all” concerned to “very concerned.” Responses from Black (N = 188) and White participants (N = 1,065) formed the base for this analysis. Concerns about unfavorable consequences of conducting psychiatric genetic studies were prevalent in the whole sample. Concern for medical insurance was most prevalent (63.4%), followed by job concern (58.8%) and stigma (57.4%). Racial discrimination was less prevalent (28.1%). Blacks endorsed significantly stronger concerns for all consequences except the medical insurance item (P < 0.008). The most significant ethnic disparity in concerns was for racial discrimination (P < 0.0001). Associations between levels of concern and ethnicity remained significant after adjustments for other factors in multivariate models. Ethnic differences (Blacks vs. Whites) in perceived concerns about unfavorable consequences from participation persist among participants in an actual psychiatric genetic study. This suggests that other factors may play a more critical role in the decision not to participate. Future studies should investigate more comprehensive sources of barriers to consenting for ongoing psychiatric genetic studies in representative samples, incorporating assessments from non‐participants as well as participants. © 2011 Wiley‐Liss, Inc.
Exploring DRD4 and its interaction with SLC6A3 as possible risk factors for adult ADHD: A meta‐analysis in four European populations
Authors: Sánchez‐Mora Cristina , Ribasés Marta , Casas Miquel , Bayés Mònica , Bosch Rosa , Fernàndez‐Castillo Noelia , Brunso Lucas , Jacobsen Kaya K. , Landaas Elisabeth T. , Lundervold Astri J. , Gross‐Lesch Silke , Kreiker Susanne , Jacob Christian P. , Lesch Klaus‐Peter , Buitelaar Jan K. , Hoogman Martine , Kiemeney Lambertus A.L.M. , Kooij J.J. Sandra , Mick Eric , Asherson Phil , Faraone Stephen V. , Franke Barbara , Reif Andreas , Johansson Stefan , Haavik Jan , Ramos‐Quiroga Josep Antoni , Cormand Bru
Published: May 2011

Attention‐deficit hyperactivity disorder (ADHD) is a common behavioral disorder affecting about 4–8% of children. ADHD persists into adulthood in around 65% of cases, either as the full condition or in partial remission with persistence of symptoms. Pharmacological, animal and molecular genetic studies support a role for genes of the dopaminergic system in ADHD due to its essential role in motor control, cognition, emotion, and reward. Based on these data, we analyzed two functional polymorphisms within the DRD4 gene (120 bp duplication in the promoter and 48 bp VNTR in exon 3) in a clinical sample of 1,608 adult ADHD patients and 2,352 controls of Caucasian origin from four European countries that had been recruited in the context of the International Multicentre persistent ADHD CollaboraTion (IMpACT). Single‐marker analysis of the two polymorphisms did not reveal association with ADHD. In contrast, multiple‐marker meta‐analysis showed a nominal association (P = 0.02) of the L‐4R haplotype (dup120bp‐48bpVNTR) with adulthood ADHD, especially with the combined clinical subtype. Since we previously described association between adulthood ADHD and the dopamine transporter SLC6A3 9R‐6R haplotype (3′UTR VNTR‐intron 8 VNTR) in the same dataset, we further tested for gene × gene interaction between DRD4 and SLC6A3. However, we detected no epistatic effects but our results rather suggest additive effects of the DRD4 risk haplotype and the SLC6A3 gene. © 2011 Wiley‐Liss, Inc.
White matter lesions defined by diffusion tensor imaging in older adults
Authors: Back Stephen A. , Kroenke Christopher D. , Sherman Larry S. , Lawrence Gus , Gong Xi , Taber Erin N. , Sonnen Joshua A. , Larson Eric B. , Montine Thomas J.
Published: May 2011

Objective:

The cellular and molecular mechanisms underlying magnetic resonance imaging‐defined white matter (WM) changes associated with age‐related cognitive decline remain poorly defined. We tested the hypothesis that WM lesions in older adults, defined by diffusion tensor imaging (DTI), arise in the setting of vascular brain injury (VBI) and are characterized by increased free radical injury and aberrant oligodendrocyte lineage (OL) cell response to injury.

Methods:

We undertook a multimodal analysis of prefrontal cortex (PFC) WM from 25 autopsies derived from a population‐based cohort where VBI and Alzheimer disease (AD) frequently coincide. Ex vivo high field strength DTI measurements of fractional anisotropy (FA), apparent diffusion coefficient, and axial and radial (D⊥) diffusivity were measured at high magnetic field strength (11.7T) and analyzed relative to quantitative in vivo biomarkers of free radical injury, an OL‐specific marker Olig2, and histologic evaluation of hyaluronan (HA), an inhibitor of OL maturation.

Results:

Coincident AD and VBI showed significant association with lower FA and a robust relationship between decreasing FA and increasing D⊥. Free radical injury to docosahexaenoate and adrenate in PFC WM was significantly elevated in cases with VBI independent of AD, and was inversely correlated with FA. Similarly, increased density of Olig2‐immunoreactive cells in PFC WM was significantly associated with VBI independent of AD and colocalized with regions enriched in HA.

Interpretation:

DTI‐defined PFC WM lesions in older individuals are characterized by free radical injury to myelin and neuroaxonal elements that coincides with pronounced expansion of the pool of OL cells in HA‐rich regions. ANN NEUROL 2011;70: 465–476.
Sulfonamide‐derived compounds and their transition metal complexes: synthesis, biological evaluation and X‐ray structure of 4‐bromo‐2‐[(E)‐{4‐[(3,4‐dimethylisoxazol‐5 yl)sulfamoyl]phenyl} iminiomethyl] phenolate
Authors: Chohan Zahid H. , Shad Hazoor A.
Published: May 2011

Sulfonamide‐derived new ligands, 4‐({[(E)‐(5‐bromo‐2‐hydroxyphenyl)methylidene]‐amino}methyl)benzenesulfonamide and 4‐bromo‐2‐((E)‐{4‐[(3,4‐dimethylisoxazol‐5‐yl)sulfamoyl]phenyl}iminiomethyl)phenolate and their transition metal [cobalt(II), copper(II), nickel(II) and zinc(II)] complexes were synthesized and characterized. The nature of bonding and structure of all the synthesized compounds were deduced from physical (magnetic susceptibility and conductivity measurements), spectral (IR, 1H and 13C NMR, electronic, mass spectrometry) and analytical (CHN analysis) data. The structure of the ligand, 4‐bromo‐2‐((E)‐{4‐[(3,4‐dimethylisoxazol‐5‐yl)sulfamoyl]phenyl} iminiomethyl)phenolate was also determined by X‐ray diffraction method. An octahedral geometry was suggested for all the complexes. In order to evaluate the biological activity of the ligands and the effect of metals, the ligands and their metal complexes were screened for in vitro antibacterial, antifungal and cytotoxic activity. The results of these studies revealed that all compounds showed moderate to significant antibacterial activity against one or more bacterial strains and good antifungal activity against various fungal strains. Copyright © 2011 John Wiley & Sons, Ltd.
Application of π‐Extended Ferrocene with Varied Anchoring Groups as Photosensitizers in TiO2‐Based Dye‐Sensitized Solar Cells (DSSCs)
Authors: Chauhan Ratna , Trivedi Manoj , Bahadur Lal , Kumar Abhinav
Published: May 2011

Two new compounds, FcCHNC6H4COOH (1) and FcCHNCH2CH2OH (2) (Fc=C5H4FeC5H5), have been synthesized and characterized by elemental analyses, IR and 1H NMR spectroscopy, and ESI‐MS. Attempt has been made to explain their quasi‐reversible redox behavior evidenced by cyclic voltammetry using density functional theory (DFT) calculations. Light‐harvesting properties of both the compounds and also the starting material, FcCHO (3), have been studied using these compounds as photosensitizers in TiO2‐based dye‐sensitized solar cells having either a propylene carbonate‐based electrolyte or ionic liquid electrolyte, namely, 1‐propyl‐3‐methyl imidazolium iodide (PMII). Long‐term stability of the photocurrent output of the cell using compound 1 as photosensitizer has been monitored periodically over 1400 h.
Stereoaligned Epitaxial Growth of Single‐Crystalline Platinum Nanowires by Chemical Vapor Transport
Authors: Yoo Youngdong , Han Sol , Kim Minjung , Kang Taejoon , In Juneho , Kim Bongsoo
Published: May 2011

Epitaxial Pt nanowire (NW) arrays are synthesized for the first time by a chemical vapor transport method by using a metal halide as a precursor. Here we report that the epitaxial growth direction of NWs can be steered by seed crystal morphology. Octahedral seeds grow into inclined NWs possessing six growth directions, whereas half‐octahedral seeds grow into vertical and horizontal NWs. Interfacial energies between the seed material and the substrate are critical in determining the morphology of seed crystals. We also demonstrate that non‐SERS‐active Pt NWs can show strong surface‐enhanced Raman scattering (SERS) spectra by placing them on Ag films. The active SERS observation would help to elucidate platinum‐catalyzed chemical reactions.
Synthesis of Terpolymers by Click Reactions
Authors: Altintas Ozcan , Tunca Umit
Published: May 2011

Well‐defined polymeric structures were easily generated through living polymerization systems, in particular, living radical polymerizations. The polymeric precursors with orthogonal functionalities were subsequently clicked together with single or double (combinatorial) click reactions, such as the copper‐catalyzed azide–alkyne cycloadditions (CuAAC) and Diels–Alder reactions, to create a wide variety of linear and nonlinear terpolymers.
Expression analysis of some genes regulated by retinoic acid in controls and triadimefon‐exposed embryos: is the amphibian Xenopus laevis a suitable model for gene‐based comparative teratology?
Authors: Di Renzo Francesca , Rossi Federica , Bacchetta Renato , Prati Mariangela , Giavini Erminio , Menegola Elena
Published: May 2011

BACKGROUND: The use of nonmammal models in teratological studies is a matter of debate and seems to be justified if the embryotoxic mechanism involves conserved processes. Published data on mammals and Xenopus laevis suggest that azoles are teratogenic by altering the endogenous concentration of retinoic acid (RA). The expression of some genes (Shh, Ptch‐1, Gsc, and Msx2) controlled by retinoic acid is downregulated in rat embryos exposed at the phylotypic stage to the triazole triadimefon (FON). In order to propose X. laevis as a model for gene‐based comparative teratology, this work evaluates the expression of Shh, Ptch‐1, Gsc, and Msx2 in FON‐exposed X. laevis embryos. METHODS: Embryos, exposed to a high concentration level (500 µM) of FON from stage 13 till 17, were examined at stages 17, 27, and 47. Stage 17 and 27 embryos were processed to perform quantitative RT‐PCR. RESULTS: The developmental rate was never affected by FON at any considered stage. FON‐exposed stage 47 larvae showed the typical craniofacial malformations. A significant downregulation of Gsc was observed in FON‐exposed stage 17 embryos. Shh, Ptch‐1, Msx2 showed a high fluctuation of expression both in control and in FON‐exposed samples both at stages 17 and 27. CONCLUSION: The downregulation of Gsc mimics the effects of FON on rat embryos, showing for this gene a common effect of FON in the two vertebrate classes. The high fluctuation observed in the gene expression of the other genes, however, suggests that X. laevis at this stage has limited utility for gene‐based comparative teratology. Birth Defects Res (Part B) 92:189–194, 2011. © 2011 Wiley‐Liss, Inc.
Developmental toxicity of Citrus aurantium in rats
Authors: Hansen Deborah K. , Juliar Beth E. , White Gene E. , Pellicore Linda S.
Published: May 2011

BACKGROUND: Ephedra was commonly used in herbal products marketed for weight loss until safety concerns forced its removal from products. Even before the ban, manufacturers had begun to replace ephedra with other compounds, including Citrus aurantium, or bitter orange. The major component in the bitter orange extract is synephrine which is chemically similar to ephedrine. The purpose of this study was to determine if relatively pure synephrine or synephrine present as a constituent of a bitter orange extract produced developmental toxicity in rats. METHOD: Sprague‐Dawley rats were dosed daily by gavage with one of several different doses of synephrine from one of two different extracts. Caffeine was added to some doses. Animals were sacrificed on GD 21, and fetuses were examined for the presence of various developmental toxic endpoints. RESULTS AND CONCLUSION: At doses up to 100 mg synephrine/kg body weight, there were no adverse effects on embryolethality, fetal weight, or incidences of gross, visceral, or skeletal abnormalities. There was a decrease in maternal weight at 50 mg synephrine/kg body weight when given as the 6% synephrine extract with 25 mg caffeine/kg body weight; there was also a decrease in maternal weight in the caffeine only group. This decrease in body weight may have been due to decreased food consumption which was also observed in these two groups. Overall, doses of up to 100 mg synephrine/kg body weight did not produce developmental toxicity in Sprague‐Dawley rats. Birth Defects Res (Part B) 92:216–223, 2011. © 2011 Wiley‐Liss, Inc.
Green fluorescent protein (GFP) leakage from microbial biosensors provides useful information for the evaluation of the scale‐down effect
Authors: Delvigne Frank , Brognaux Alison , Francis Frédéric , Twizere Jean‐Claude , Gorret Nathalie , Sorensen Soren J. , Thonart Philippe
Published: May 2011

Mixing deficiencies can be potentially detected by the use of a dedicated whole cell microbial biosensor. In this work, a csiE promoter induced under carbon‐limited conditions was involved in the elaboration of such biosensor. The cisE biosensor exhibited interesting response after up and down‐shift of the dilution rate in chemostat mode. Glucose limitation was accompanied by green fluorescent protein (GFP) leakage to the extracellular medium. In order to test the responsiveness of microbial biosensors to substrate fluctuations in large‐scale, a scale‐down reactor (SDR) experiment was performed. The glucose fluctuations were characterized at the single cell level and tend to decrease the induction of GFP. Simulations run on the basis of a stochastic hydrodynamic model have shown the variability and the frequencies at which biosensors are exposed to glucose gradient in the SDR. GFP leakage was observed to a great extent in the case of a culture operated in well‐mixed fed‐batch mode, by comparison with those operated in SDR. GFP leakage seems to be correlated to a higher membrane permeability, confirming previous studies highlighting a better cell viability in cultures operated in a fluctuating environment. Our results suggest that GFP leakage could be used in parallel to the normal GFP biosensor function in order to assess microbial viability in process conditions.
Empirical model and in vivo characterization of the bacterial response to synthetic gene expression show that ribosome allocation limits growth rate
Authors: Carrera Javier , Rodrigo Guillermo , Singh Vijai , Kirov Boris , Jaramillo Alfonso
Published: May 2011

Synthetic biology uses modeling to facilitate the design of new genetic constructions. In particular, it is of utmost importance to model the reaction of the cellular chassis when expressing heterologous systems. We constructed a mathematical model for the response of a bacterial cell chassis under heterologous expression. For this, we relied on previous characterization of the growth‐rate dependence on cellular resource availability (in this case, DNA and RNA polymerases and ribosomes). Accordingly, we estimated the maximum capacities of the cell for heterologous expression to be 46% of the total RNA and the 33% of the total protein. To experimentally validate our model, we engineered two genetic constructions that involved the constitutive expression of a fluorescent reporter in a vector with a tunable origin of replication. We performed fluorescent measurements using population and single‐cell fluorescent measurements. Our model predicted cell growth for several heterologous constructions under five different culture conditions and various plasmid copy numbers with significant accuracy, and confirmed that ribosomes act as the limiting resource. Our study also confirmed that the bacterial response to synthetic gene expression could be understood in terms of the requirement for cellular resources and could be predicted from relevant cellular parameters.
Design and Synthesis of “Dumb‐bell” and “Triangular” Inorganic–Organic Hybrid Nanopolyoxometalate Clusters and Their Characterisation through ESI‐MS Analyses
Authors: Pradeep Chullikkattil P. , Li Feng‐Yan , Lydon Claire , Miras Haralampos N. , Long De‐Liang , Xu Lin , Cronin Leroy
Published: May 2011

A series of tris(hydroxymethyl)aminomethane (TRIS)‐based linear (bis(TRIS)) and triangular (tris(TRIS)) ligands has been synthesised and were covalently attached to the Wells–Dawson type cluster [P2V3W15O62]9− to generate a series of nanometer‐sized inorganic–organic hybrid polyoxometalate clusters. These huge hybrids, with a molecular mass similar to that of small proteins in the range of ≈10–16 kDa, were unambiguously characterised by using high‐resolution ESI‐MS. The ESI‐MS spectra of these compounds revealed, in negative ion mode, a characteristic pattern showing distinct groups of peaks corresponding to different anionic charge states ranging from 3− to 8− for the hybrids. Each peak in these individual groups could be unambiguously assigned to the corresponding hybrid cluster anion with varying combinations of tetrabutylammonium (TBA) and other cations. This study therefore highlights the prowess of the high‐resolution ESI‐MS for the unambiguous characterisation of large, nanoscale, inorganic–organic hybrid clusters that have huge mass, of the order of 10–16 kDa. Also, the designed synthesis of these compounds points to the fact that we were able to achieve a great deal of structural pre‐design in the synthesis of these inorganic–organic hybrid polyoxometalates (POMs) by means of a ligand design route, which is often not possible in traditional “one‐pot” POM synthesis.
Process Intensification in Fluid Separation Processes
Authors: Keller Tobias , Roth Tim , Mackowiak Jan F. , Kreis Peter , Górak Andrzej , Stankiewicz A.
Published: May 2011

Prozessintensivierung verfolgt im Wesentlichen vier verschiedene Ziele: die Effizienz von intra‐ und intermolekularen Wechselwirkungen maximieren, den Durchlauf einheitlicher Prozesswege für jedes Molekül sicherstellen, Triebkräfte und Phasengrenzflächen optimieren und Synergieeffekte zwischen Teilprozessen maximieren. Jedes dieser Ziele kann auf insgesamt vier fundamentalen Ebenen erreicht werden: auf einer räumlichen, thermodynamischen, zeitlichen und funktionalen Ebene. Der vorliegende Artikel gibt eine Übersicht, wie sich die Ziele der Prozessintensivierung in der Fluidverfahrenstechnik erreichen lassen. Dabei wird jede der vier Ebenen separat über alle relevanten Zeit‐ und Längenskalen hinweg von den Molekülen bis hin zur verfahrenstechnischen Anlage betrachtet.
Structure and Catalysis of Cellulose‐Derived Amorphous Carbon Bearing SO3H Groups
Authors: Fukuhara Kiichi , Nakajima Kiyotaka , Kitano Masaaki , Kato Hideki , Hayashi Shigenobu , Hara Michikazu
Published: May 2011

The correlation between catalytic performance and structure of a cellulose‐derived and carbon‐based solid acid (CCSA), an amorphous carbon bearing SO3H, COOH, and phenolic OH groups, was investigated. Sulfonation of partially carbonized cellulose under a N2 atmosphere resulted in the formation of a CCSA, which was amorphous carbon consisting of small polycyclic aromatic carbon sheets with a high density of SO3H groups (ca. 2 mmol g−1). CCSAs were prepared from carbon precursors, which were obtained at temperatures ≤723 K, and exhibited a high catalytic performance for the esterification of acetic acid with ethanol and for the hydrolysis of cellobiose, although the surface areas were small (<5 m2 g−1). In contrast, CCSAs, which were prepared from carbon precursors obtained at ≥823 K, exhibited much lower catalytic activities for both reactions, although the CCSAs had sufficient amounts of SO3H groups. Structural analyses, including spectroscopic analysis of CCSAs with adsorbed probe molecules, revealed that cross‐linking between the polycyclic aromatic carbon sheets caused the sharp decrease in activity.
Cell fixation in zinc salt solution is compatible with DNA damage response detection by phospho‐specific antibodies
Authors: Zhao Hong , Li Jiangwei , Traganos Frank , Halicka H. Dorota , Zarebski Mirosław , Dobrucki Jurek , Darzynkiewicz Zbigniew
Published: May 2011

By virtue of superior preservation of proteins and nucleic acids the zinc salt‐based fixatives (ZBF) has been proposed as an alternative to precipitants and cross‐linking fixatives in histopathology. It was recently reported that ZBF is compatible with analysis of cell surface immunophenotype and detection of intracellular epitopes by flow cytometry. The aim of this study was to explore whether ZBF is also compatible with the detection of DNA damage response assessed by phospho‐specific antibodies (Abs) detecting phosphorylation of the key proteins of that pathway. DNA damage in human pulmonary adenocarcinoma A549 cells was induced by treatment with the DNA topoisomerase I inhibitor camptothecin and phosphorylation of histone H2AX on Ser139 (γH2AX) and of ATM on Ser1981 was detected with phospho‐specific Abs; cellular fluorescence was measured by laser scanning cytometry (LSC). The sensitivity and accuracy of detection of H2AX and ATM phosphorylation concurrent with the detection of DNA replication by EdU incorporation and “click chemistry” was found in ZBF fixed cells to be comparable to that of cell fixed in formaldehyde. The accuracy of DNA content measurement as evident from the resolution of DNA content frequency histograms of cells stained with DAPI was somewhat better in ZBF‐ than in formaldehyde‐fixed cells. The pattern of chromatin condensation revealed by the intensity of maximal pixel of DAPI that allows one to identify mitotic and immediately post‐mitotic cells by LSC was preserved after ZBF fixation. ZBF fixation was also compatible with the detection of γH2AX foci considered to be the hallmarks of induction of DNA double‐strand breaks. Analysis of cells by flow cytometry revealed that ZBF fixation of lymphoblastoid TK6 cells led to about 60 and 33% higher intensity of the side and forward light scatter, respectively, compared to formaldehyde fixed cells. © 2011 International Society for Advancement of Cytometry
Ethanol‐mediated appetitive conditioning in infant rats, but not corticosterone release, is dependent on route of ethanol administration
Authors: Pautassi Ricardo Marcos , Nizhnikov Michael Eduard , Spear Norman E.
Published: May 2011

A recent study found appetitive reinforcement in infant rats given 1.0 but not 2.0 g/kg ethanol and only when ethanol was delivered intragastrically (i.g., but not if intraperitoneally, i.p.; Nizhnikov, Pautassi, Truxell, & Spear [2009] Alcohol 43, 347–358). Corticosterone release could modulate ethanol's motivational effects. The goal of this study was to replicate the differential capability of i.g. vs. i.p. ethanol to induce conditioning and to find hormonal correlates underlying this phenomenon. Experiment 1 confirmed that 1.0 g/kg ethanol induced conditioned preference in infant rats when given i.g. but not i.p. In Experiment 2 corticosterone was assessed at 20, 40, 60, or 120 min after ethanol (0.0, 0.5, 1.0, and 2.0 g/kg, i.g. or i.p.). Route of administration failed to alter corticosterone release. The 2.0 g/kg, but not 0.5 or 1.0 g/kg, ethanol dose evoked heightened corticosterone release. The results confirm the differing motivational effects associated with i.g. and i.p. ethanol. These effects do not seem to be related to differential corticosterone responsiveness. © 2011 Wiley Periodicals, Inc. Dev Psychobiol 54:98–104, 2012.
The visual system of zebrafish and its use to model human ocular Diseases
Authors: Gestri Gaia , Link Brian A. , Neuhauss Stephan C.F.
Published: May 2011

Free swimming zebrafish larvae depend mainly on their sense of vision to evade predation and to catch prey. Hence, there is strong selective pressure on the fast maturation of visual function and indeed the visual system already supports a number of visually driven behaviors in the newly hatched larvae. The ability to exploit the genetic and embryonic accessibility of the zebrafish in combination with a behavioral assessment of visual system function has made the zebrafish a popular model to study vision and its diseases. Here, we review the anatomy, physiology, and development of the zebrafish eye as the basis to relate the contributions of the zebrafish to our understanding of human ocular diseases. © 2011 Wiley Periodicals, Inc. Develop Neurobiol 72: 302–327, 2012
Isolation and cytogenetic characterization of zebrafish meiotic prophase I mutants
Authors: Saito Kenji , Siegfried Kellee R. , Nüsslein‐Volhard Christiane , Sakai Noriyoshi
Published: May 2011

We describe here the isolation and cytogenetic characterization of three meiotic prophase I mutants, denoted ietsugu (its), iesada (isa), and iemochi (imo), isolated by a novel N‐ethyl‐N‐nitrosourea mutagenesis screen for adult zebrafish gonadogenesis. Histological examination and flow cytometry analysis of testes from these mutants showed that each contained neither spermatids nor sperm. Staining for Sycp3 and cleaved Caspase‐3 and TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridinetriphosphate nick end‐labeling) assay further revealed that its had defects at the onset of meiosis, and that isa and imo spermatocytes failed to progress past the zygotene stage with apoptosis occurring in the testicular somatic cells. Staining for phosphorylated histone H2AX showed that foci formation in leptotene spermatocytes was disrupted in isa and imo. Furthermore, in vitro differentiation experiments revealed the possibility that the defects and sterility associated with mutations were germ line autonomous. Our results thus indicate that each responsible gene is necessary for meiotic progression during spermatogenesis and for male fertility. Developmental Dynamics 240:1779–1792, 2011. © 2011 Wiley‐Liss, Inc.