bluuebunny/crossref_metadata_2025 huggingface dataset:
A review of studies on androgen and estrogen exposure in fish early life stages: effects on gene and hormonal control of sexual differentiation
Authors: Leet Jessica K. , Gall Heather E. , Sepúlveda Maria S.
Published: May 2011

Teleost fish are unique among vertebrates in that phenotypic sex or onset of sex inversion can be easily manipulated by hormonal treatments. In recent years, researchers have begun reporting concentrations of synthetic and natural hormones in the environment. Although concentrations are very low (in the parts per trillion to low parts per billion), they are still of concern because of the high potency of synthetic hormones and the enhanced susceptibility of teleost fishes, especially early life stages, to hormonal exposures. In this review, we will focus on sex differentiation in teleost fishes and how these processes in fish early life stages may be impacted by environmental hormones which are known to contaminate aquatic environments. We will start by reviewing information on sources and concentrations of hormones in the environment and continue by summarizing the state of knowledge of sex differentiation in teleost gonochoristic fishes, including information on genes involved (e.g. cyp19, dmrt1, sox9 and foxl2). We will end our review with a summary of studies that have examined the effects of androgens and estrogens on fish sex differentiation after exposure of fish embryos and larvae and with ideas for future research. Copyright © 2011 John Wiley & Sons, Ltd.
AMP‐activated protein kinase inhibits TGF‐β‐induced fibrogenic responses of hepatic stellate cells by targeting transcriptional coactivator p300
Authors: Lim Joong‐Yeon , Oh Min‐A , Kim Won Ho , Sohn Hee‐Young , Park Sang Ick
Published: May 2011

Liver fibrosis is a common consequence of various chronic liver injuries, including virus infection and ethanol. Activated hepatic stellate cells (HSCs) contribute to liver fibrosis through the accumulation of extracellular matrix proteins, including type I alpha collagen (COL1A). The activation of adenosine monophosphate‐activated protein kinase (AMPK) modulates HSCs activation, but its underlying mechanism remains unclear. Here, we report that AMPK inhibits transforming growth factor (TGF)‐β‐induced fibrogenic property of HSCs by regulating transcriptional coactivator p300. We treated human (LX‐2) and rat (CFSC‐2G) HSC lines with TGF‐β to induce fibrogenic activation of HSCs. Pharmacological activation of AMPK by treatment with 5‐aminoimidazole‐4‐carboxamide‐1‐beta‐4‐ribofuranoside (AICAR), metformin, or adiponectin lowered TGF‐β‐induced expression of COL1A and myofibroblast marker alpha‐smooth muscle actin (α‐SMA). Transient transduction of constitutively active AMPKα (caAMPKα) was sufficient to attenuate COL1A and α‐SMA expression, whereas an AMPK inhibitor considerably abrogated the inhibitory effect of AICAR on fibrogenic gene expression. Although AMPK significantly suppressed Smad‐dependent transcription, it did not affect TGF‐β‐stimulated phosphorylation, nuclear localization, or DNA‐binding activity of Smad2/3. AICAR rather attenuated TGF‐β‐induced Smad3 interaction with transcriptional coactivator p300 accompanying with reduction of Smad3 acetylation. Moreover, AICAR induced not only physical interaction between AMPK and p300 but also proteasomal degradation of p300 protein. Our data provide substantial evidence that AMPK could be a novel therapeutic target for treatment of liver fibrosis, by demonstrating the underlying mechanism of AMPK‐induced antifibrotic function in HSCs. J. Cell. Physiol. 227: 1081–1089, 2012. © 2011 Wiley Periodicals, Inc.
Tensile force inhibits the proliferation of human periodontal ligament fibroblasts through Ras‐p38 MAPK up‐regulation
Authors: Kook Sung‐Ho , Lee Jeong‐Chae
Published: May 2011

The capacity of human periodontal ligament fibroblasts (PLF) to proliferate in response to mechanical force plays a critical role in orthodontic tooth movement. Extensive research has not fully revealed the mechanisms by which the PLF respond to mechanical force. The responses to force differ according to the origin of cells and the type of stress applied. In this study, we examined the proliferative response of PLF to tensile force. We also explored cellular mechanisms involved in the mechanosignal transduction of tensile force. Application to the force to PLF with 1.5% elongation for 1 h inhibited cell proliferation. This was accompanied by reductions in several cyclins and cyclin‐dependent kinases (CDKs) involved in the G1/S transition; however, p21 knockdown prevented these events. Pharmacological inhibitor of p38 MAPK suppressed the force‐mediated growth inhibition as well as the decrease in p21 expression. Ras inhibitor almost completely blocked the tension‐mediated increases in p‐p38 MAPK and p‐p21, and the attendant increase in PLF proliferation. These findings suggest that tension force activates Ras‐p38 MAPK pathways in PLF, which up‐regulate p21 and arrest cell cycle progression at the G1phase. J. Cell. Physiol. 227: 1098–1106, 2012. © 2011 Wiley Periodicals, Inc.
Synthesis and antimicrobial studies of pyrazolyl oxadiazoles and thiadiazoles
Authors: Padmavathi Venkatapuram , Reddy Sanapalli Nagi , Reddy Guda Dinneswara , Venkatesh Bhumireddy Chinnachennaiahgari , Padmaja Adivireddy
Published: May 2011

A new class of bis heterocycles—sulfone linked pyrazolyl oxadiazoles thiadiazoles were prepared from E‐phenylsulfonylethenesulfonylacetic acid and studied their antimicrobial activities. J. Heterocyclic Chem., (2011).
Synthesis and antiviral activity of new substituted pyrimidine glycosides
Authors: Ramiz Mahmoud M. M. , El‐Sayed Wael A. , Hagag Ezzat , Abdel‐Rahman Adel A.‐H.
Published: May 2011

A number of N‐substituted pyrimidine glycosides were synthesized by coupling reaction of the pyrimidine base with acetobromosugars followed by deprotection. The synthesized compounds were tested for their antiviral activity against Hepatitis B Virus (HBV). Plaque reduction infectivity assay was used to determine virus count reduction as a result of treatment with tested compounds which showed moderate to high anti viral activities. J. Heterocyclic Chem., (2011).
Cross sectional geometry of the forelimb skeleton and flight mode in pelecaniform birds
Authors: Simons Erin L. R. , Hieronymus Tobin L. , O'Connor Patrick M.
Published: May 2011

Avian wing elements have been shown to experience both dorsoventral bending and torsional loads during flapping flight. However, not all birds use continuous flapping as a primary flight strategy. The pelecaniforms exhibit extraordinary diversity in flight mode, utilizing flapping, flap‐gliding, and soaring. Here we (1) characterize the cross‐sectional geometry of the three main wing bone (humerus, ulna, carpometacarpus), (2) use elements of beam theory to estimate resistance to loading, and (3) examine patterns of variation in hypothesized loading resistance relative to flight and diving mode in 16 species of pelecaniform birds. Patterns emerge that are common to all species, as well as some characteristics that are flight‐ and diving‐mode specific. In all birds examined, the distal most wing segment (carpometacarpus) is the most elliptical (relatively highImax/Imin) at mid‐shaft, suggesting a shape optimized to resist bending loads in a dorsoventral direction. As primary flight feathers attach at an oblique angle relative to the long axis of the carpometacarpus, they are likely responsible for inducing bending of this element during flight. Moreover, among flight modes examined the flapping group (cormorants) exhibits more elliptical humeri and carpometacarpi than other flight modes, perhaps pertaining to the higher frequency of bending loads in these elements. The soaring birds (pelicans and gannets) exhibit wing elements with near‐circular cross‐sections and higher polar moments of area than in the flap and flap‐gliding birds, suggesting shapes optimized to offer increased resistance to torsional loads. This analysis of cross‐sectional geometry has enhanced our interpretation of how the wing elements are being loaded and ultimately how they are being used during normal activities. J. Morphol., 2011. © 2011 Wiley‐Liss,Inc.
Diverse origin of P[19] rotaviruses in children with acute diarrhea in Taiwan: Detection of novel lineages of the G3, G5, and G9 VP7 genes
Authors: Wu Fang‐Tzy , Bányai Krisztián , Huang Jason C. , Wu Ho‐Sheng , Chang Feng‐Yee , Yang Jyh‐Yuan , Hsiung Chao Agnes , Huang Yhu‐Chering , Lin Jen‐Shiou , Hwang Kao‐Pin , Jiang Baoming , Gentsch Jon R.
Published: May 2011

We previously reported the detection of genotype P[19] rotavirus strains from children hospitalized with acute dehydrating diarrhea during a 5‐year surveillance period in Taiwan. The characterization of five P[19] strains (0.4% of all typed), including three G3P[19], a novel G5P[19], and a unique G9P[19] genotype is described in this study. Phylogenetic analysis of the VP4, VP7, VP6, and NSP4 genes was performed, which demonstrated novel lineages for respective genotypes of the VP4 and the VP7 genes. The sequence similarities of the P[19] VP4 gene among Taiwanese human strains was higher (nt, 91.5–96.2%; aa, 93.7–97.6%) than to other P[19] strains (nt, 83.5–86.6%; aa, 89.4–94.1%) from different regions of the world. The VP7 gene of the three G3P[19] Taiwanese strains shared up to 93.4% nt and 97.5% aa identity to each other but had lower similarity to reference strain sequences available in GenBank (nt, <90.1%; aa, <95.6%). Similarly, the VP7 gene of the novel G5P[19] strain was only moderately related to the VP7 gene of reference G5 strains (nt, 82.2–87.3%; aa, 87.0–93.1%), while the VP7 gene of the single G9P[19] strain was genetically distinct from other known human and animal G9 rotavirus strains (nt, ≤92.0%; aa, ≤95.7%). Together, these findings suggest that the Taiwanese P[19] strains originated by independent interspecies transmission events. Synchronized surveillance of human and animal rotaviruses in Taiwan should identify possible hosts of these uncommon human rotavirus strains. J. Med. Virol. 83:1279–1287, 2011. © 2011 Wiley‐Liss, Inc.
Correlation of serum hepatitis B surface antigen level with response to entecavir in naïve patients with chronic hepatitis B
Authors: Lee Myoung Hee , Lee Da Mi , Kim Soon Sun , Cheong Jae Youn , Cho Sung Won
Published: May 2011

Recent studies have suggested that quantifying the serum HBsAg levels can predict the response to pegylated interferon. We aimed to determine the change in serum HBsAg levels during entecavir (ETV) treatment and the correlation with treatment response in chronic HBeAg‐positive and HBeAg‐negative hepatitis B patients. Serial HBsAg levels were measured using the Architect assay (Abbott Laboratories, Abbott Park, IL) in sera from 101 treatment‐naive chronic hepatitis B (CHB) patients receiving ETV. During treatment, in HBeAg‐positive patients, the mean HBsAg level was 3.51, 3.22, 3.34, 3.36, and 3.40 log10 IU/ml at baseline, 3, 6, 12, and 24 months, respectively, and there was no significant change compared with the baseline level, except the decline at 3 months (P = 0.009). In HBeAg‐negative patients, the mean level of serum HBsAg showed increase with 3.06, 3.09, 3.20, 3.26, and 3.27 log10 IU/ml at baseline, 3, 6, 12, and 24 months of treatment, respectively. In HBeAg‐positive patients, HBV‐DNA negativity (<2,000 copies/ml; P = 0.010) and HBsAg level <3,000 IU/ml (P = 0.026) at 3 months were independent predictors of HBeAg loss/seroconversion at 12 months. After 24 months of treatment, the HBsAg levels at baseline (P = 0.046) was an independent factor of HBeAg loss/seroconversion. In HBeAg‐negative patients, undetectable HBV DNA at 6 months was an independent factor predicting undetectable HBV DNA after 12 months of therapy. The level of serum HBsAg before and during therapy was a good predictor of HBeAg loss/seroconversion in naïve HBeAg‐positive CHB patients receiving entecavir. J. Med. Virol. 83:1178–1186, 2011. © 2011 Wiley‐Liss, Inc.
Qualitative and quantitative analyses of Epimedium wushanense by high‐performance liquid chromatography coupled with diode array detection and electrospray ionization tandem mass spectrometry
Authors: Li Hui‐fang , Guan Xiang‐yu , Ye Min , Xiang Cheng , Lin Chang‐hu , Sun Chao , Guo De‐an
Published: May 2011

A new HPLC‐DAD‐ESI‐MSn method was developed for rapid separation, characterization and quantitation of flavonoids in Epimedium wushanense, a popular Chinese herbal medicine. For qualitative identification, a total of 37 compounds were characterized from the underground and aerial parts of E. wushanense. Among them, 28 compounds were prenylated flavonoids, and 23 were confirmed by comparing with reference standards. For quantitative analysis, 12 major flavonoids including kaempferol glycosides, desmethylicaritin glycosides, and icaritin glycosides were simultaneously determined by HPLC/UV. Samples were separated on a Waters Symmetry C18 column at 35°C eluted with a gradient three‐component mobile phase of acetonitrile, methanol, and water containing 0.03% v/v formic acid. All the flavonoids showed good linearity (r2≥0.9997). The recoveries varied from 92.6 to 106.1% at three concentration levels. This method was applied to the determination of 20 samples of different geographical sources, harvesting time, and plant parts. Contents of the predominant flavonoid, epimedin C, ranged from 1.4 to 5.1% in aerial parts and 1.0 to 2.8% in underground parts. The methods established in this paper were simple and reliable and could be used for the quality control of E. wushanense.
Family Members and Vacation Satisfaction: Proposal of a Conceptual Framework
Authors: Kozak Metin , Duman Teoman
Published: May 2011

This study aimed to investigate the extent to which the other family members (spouse and/or child/ren) in a family influence the vacationers' overall vacation satisfaction and future behavioural intentions. As part of the study, a conceptual framework was proposed where overall vacation satisfaction mediates the relationships between spouses' and child/ren's vacation evaluations and respondents' return and recommending intentions. The methodology included self‐administered surveys of 445 families from the UK, which were completed at a Turkish resort airport in August 2007. The results indicate that the respondents' vacation satisfaction is influenced more strongly by spouses. Furthermore, the results show that respondents' return intentions are determined by their and their spouses' vacation satisfaction, whereas respondents' recommending intentions are determined by their and their child/ren's vacation satisfaction. These results bring new insights into the post‐purchase vacation behaviour for both theory and practice. Copyright © 2011 John Wiley & Sons, Ltd.
Rate coefficients and ClO radical yields in the reaction of O(1D) with CClF2CCl2F, CCl3CF3, CClF2CClF2, and CCl2FCF3
Authors: Baasandorj Munkhbayar , Feierabend Karl J. , Burkholder James B.
Published: May 2011

Rate coefficients, k, and ClO radical product yields, Y, for the gas‐phase reaction of O(1D) with CClF2CCl2F (CFC‐113) (k2), CCl3CF3 (CFC‐113a) (k3), CClF2CClF2 (CFC‐114) (k4), and CCl2FCF3 (CFC‐114a) (k5) at 296 K are reported. Rate coefficients for the loss of O(1D) were measured using a competitive reaction technique, with n‐butane (n‐C4H10) as the reference reactant, employing pulsed laser photolysis production of O(1D) combined with laser‐induced fluorescence detection of the OH radical temporal profile. Rate coefficients were measured to be k2 = (2.33 ± 0.40) × 10−10 cm3 molecule−1 s−1, k3 = (2.61 ± 0.40) × 10−10 cm3 molecule−1 s−1, k4 = (1.42 ± 0.25) × 10−10 cm3 molecule−1 s−1, and k5 = (1.62 ± 0.30) × 10−10 cm3 molecule−1 s−1. ClO radical product yields for reactions (2)–(5) were measured using pulsed laser photolysis combined with cavity ring‐down spectroscopy to be 0.80 ± 0.10, 0.79 ± 0.10, 0.85 ± 0.12, and 0.79 ± 0.10, respectively. The quoted errors in k and Y are at the 2σ (95% confidence) level and include estimated systematic errors. © 2011 Wiley Periodicals, Inc.*

This article is a U.S. Government work and, as such, is in the public domain of the United States of America

Int J Chem Kinet 43: 393–401, 2011
What faces reveal: Impaired affect display in facial paralysis
Authors: Ishii Lisa E. , Godoy Andres , Encarnacion Carlos O. , Byrne Patrick J. , Boahene Kofi D. O. , Ishii Masaru
Published: May 2011

Objectives/Hypothesis:

To evaluate affect display in patients with facial paralysis as compared with normal subjects. We hypothesized that patients with facial paralysis would have impaired affect display and be perceived as displaying a negative affect as compared with normal subjects.

Study Design:

Randomized controlled experiment.

Methods:

Forty naive observers viewed pictures of patients with facial paralysis and normal faces. Observers classified the affect display of the patients and normal subjects by using a survey containing choices regarding primary emotions and personal attributes.

Results:

An exploratory latent class analysis was performed on the survey results, and the faces were categorized into three types: positive, negative, and neutral. The probability of interpreting normal smiling faces as positive was 98%; the probability of interpreting those in repose as neutral or positive was 60%. The faces with facial paralysis were much more likely to be regarded as negative or neutral. The probability for classification into the negative class was 73% for the paralyzed faces in repose and 69% for the paralyzed smiling faces. In the latent class regression, smiling normal faces were six times more likely to be classified as positive, and smiling paralyzed faces were three times less likely to be in that class.

Conclusions:

Patients with facial paralysis were classified as having a negative affect display the vast majority of the time. Antithetically, normal faces in repose were classified as neutral the majority of the time; they were classified as positive the majority of the time when smiling. These novel results demonstrate the impact of the facial paralysis defect on perception by observers. Laryngoscope, 2011
Interactions Between a Luminescent Conjugated Oligoelectrolyte and Insulin During Early Phases of Amyloid Formation
Authors: Wigenius Jens , Persson Gustav , Widengren Jerker , Inganäs Olle
Published: May 2011

Aggregates of misfolded proteins play an important role in diseases such as Alzheimer's. Here it is demonstrated how the anionic oligothiophene p‐FTAA interacts with and influences pre‐fibrillar protein assemblies during the earlier stages of in vitro fibrillation. Conjugated polythiophenes have previously been demonstrated to detect and discriminate between different types of protein aggregates and also introduce luminescent or conductive properties to these nanoscale fiber structures. Fluorescence spectroscopy, DLS, TEM and FCS are employed to follow the interplay between p‐FTAA and insulin during in vitro fibrillation.

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Synthesis and Characterization of Poly(ε‐caprolactone)‐block‐poly[N‐(2‐hydroxypropyl)methacrylamide] Micelles for Drug Delivery
Authors: Krimmer Stefan G. , Pan Huaizhong , Liu Jihua , Yang Jiyuan , Kopeček Jindřich
Published: May 2011

Amphiphilic block copolymers based on HPMA and ε‐CL were synthesized by ring‐opening polymerization of ε‐CL followed by RAFT polymerization of HPMA. A copolymer composed of 34 kDa PHPMA and 8.5 kDa PCL associated into micelles with CMC of 5.4 µg · mL−1. A novel retinoid, 3‐Cl‐AHPC‐OMe, was incorporated into micelles with 25 wt.‐% loading by dialysis method. The effective diameter of drug loading micelles was 117 nm. Incubation of micelles in PBS at 37 °C indicated 86 wt.‐% of the drug was released after 96 h. Cytotoxicity studies performed with C4‐2 prostate cancer cells showed the IC50 dose was 1.96 µM after 72 h of incubation, whereas the micelles without drug showed no cytotoxicity.

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Syndiotactic Polystyrene Films: Orientation and Structural Changes Upon Biaxial Drawing
Authors: Rizzo Paola , Albunia Alexandra R.
Published: May 2011

The orientation developed in biaxially stretched sPS (BoSPS) films before and after crystallization is studied using XRD and FT‐IR. On BoSPS films, thermal treatment induces crystallization into the trans‐planar α‐crystalline phase and a “planar” crystalline phase orientation is observed. In contrast, solvent treatments on BoSPS films induce crystallization into the helical δ‐crystalline phase, representing the first example of a polymeric framework that is able to absorb low‐molecular‐mass guest molecules from water and air at low activities and that is promising for applications in chemical separation or water purification applications; in this case a high degree of a//c// “uniplanar” crystalline phase orientation is observed.

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Semiconducting Single‐Walled Carbon Nanotubes as Radical Photoinitiators
Authors: Sangermano Marco , Marino Francesco , Reuel Nigel , Strano Michael S.
Published: May 2011

Upon photoexcitation, SWNTs, which have semiconducting behavior, can generate radicals that in turn start acrylic polyaddition reactions. The high efficiency of photoinitiation of polyethyleneglycol diacrylate achieved in the presence of SWNTs is evidenced by the high acrylic double bond conversion reached in the presence of the carbon filler and confirmed by the high gel content values of the cured films. Thermal analyses show that the effect of Tg increases with increased SWNT content in the formulations. Morphology investigations show a good dispersion and distribution of the SWNTs within the polymeric coating. It is demonstrated that the use of semiconducting SWNTs can combine the advantages of using them both as the filler and photoinitiator at the same time to achieve composite materials with enhanced properties.

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Neurophysiologic studies of the sacral reflex in women with “non‐neurogenic” sacral dysfunction
Authors: Podnar Simon
Published: May 2011

Aims

To test different technical setups for stimulation and recording of the sacral reflex, provide confidence intervals and discuss the utility of the sensory threshold and the sacral reflex threshold in women with “non‐neurogenic” sacral dysfunction.

Methods

All women without neurologic disorder, with normal neurologic examination, and bilaterally normal quantitative electromyography of the external anal sphincter (EAS) muscles referred consecutively for uro‐neurophysiologic testing were included. The sacral reflex was elicited by single and double electrical stimulation of the clitoris, and the response detected by a needle electrode inserted separately into the left and right bulbocavernosus muscle (i.e., clitoro‐cavernosus reflex), and in some women also inserted into the EAS muscle.

Results

Thirty‐one women, mainly with fecal and/or urinary incontinence, were studied. Recording of the sacral reflex from the bulbocavernosus muscle was found to be much clearer than from the sphincter muscles. On 13 sides on single and on 6 sides on double pulse electrical stimuli clitoro‐cavernosus reflex latencies were found to be much longer compared to those obtained previously in women with intact sacral function.

Conclusions

The present study supports the findings of previous studies, which reported longer sacral reflex latencies in women with “non‐neurogenic” sacral dysfunction. The difference might be explained by the lower excitation level of the sacral spinal cord neurons in some women with incontinence. Women with sacral dysfunction and prolonged sacral reflex latency need to be examined neurologically and electromyographically to confirm proximal neuropathic lesion. Neurourol. Urodynam. 30: 1603–1608, 2011. © 2011 Wiley Periodicals, Inc.
Perineal surface electromyography does not typically demonstrate expected relaxation during normal voiding
Authors: Kirby Anna C. , Nager Charles W. , Litman Heather J. , FitzGerald Mary P. , Kraus Stephen , Norton Peggy , Sirls Larry , Rickey Leslie , Wilson Tracey , Dandreo Kimberly J. , Shepherd Jonathan , Zimmern Philippe ,   for the Urinary Incontinence Treatment Network
Published: May 2011

Aims

To describe perineal surface patch electromyography (EMG) activity during urodynamics (UDS) and compare activity between filling and voiding phases and to assess for a relationship between preoperative EMG activity and postoperative voiding symptoms.

Methods

655 women underwent standardized preoperative UDS that included perineal surface EMG prior to undergoing surgery for stress urinary incontinence. Pressure‐flow studies were evaluated for abdominal straining and interrupted flow. Quantitative EMG values were extracted from 10 predetermined time‐points and compared between fill and void. Qualitative EMG activity was assessed for the percent of time EMG was active during fill and void and for the average amplitude of EMG during fill compared to void. Postoperative voiding dysfunction was defined as surgical revision or catheterization more than 6 weeks after surgery. Fisher's exact test with a 5% two‐sided significance level was used to assess differences in EMG activity and postoperative voiding dysfunction.

Results

321 UDS had interpretable EMG studies, of which 131 (41%) had EMG values at all 10 predetermined and annotated time‐points. Quantitative and qualitative EMG signals during flow were usually greater than during fill. The prevalence of postoperative voiding dysfunction in subjects with higher preoperative EMG activity during void was not significantly different. Results were similar in the 42 subjects who had neither abdominal straining during void nor interrupted flow.

Conclusions

Perineal surface patch EMG did not measure expected pelvic floor and urethral sphincter relaxation during voiding. Preoperative EMG did not predict patients at risk for postoperative voiding dysfunction. Neurourol. Urodynam. 30: 1591–1596, 2011. © 2011 Wiley Periodicals, Inc.
Multiscale method for characterization of porous microstructures and their impact on macroscopic effective permeability
Authors: Sun W. C. , Andrade J. E. , Rudnicki J. W.
Published: May 2011

Recent technology advancements on X‐ray computed tomography (X‐ray CT) offer a nondestructive approach to extract complex three‐dimensional geometries with details as small as a few microns in size. This new technology opens the door to study the interplay between microscopic properties (e.g. porosity) and macroscopic fluid transport properties (e.g. permeability). To take full advantage of X‐ray CT, we introduce a multiscale framework that relates macroscopic fluid transport behavior not only to porosity but also to other important microstructural attributes, such as occluded/connected porosity and geometrical tortuosity, which are extracted using new computational techniques from digital images of porous materials. In particular, we introduce level set methods, and concepts from graph theory, to determine the geometrical tortuosity and connected porosity, while using a lattice Boltzmann/finite element scheme to obtain homogenized effective permeability at specimen‐scale. We showcase the applicability and efficiency of this multiscale framework by two examples, one using a synthetic array and another using a sample of natural sandstone with complex pore structure. Copyright © 2011 John Wiley & Sons, Ltd.
Flame retardancy of polypropylene (nano)composites containing LDH and zinc borate
Authors: Wang Linjiang , He Xuejun , Lu Hongdian , Feng Jianxiang , Xie Xiangli , Su Shengpei , Wilkie Charles A
Published: May 2011

Polypropylene (PP)/organically‐modified layered double hydroxides (LDH) and PP/organo‐LDH/zinc borate (BZn) (nano)composites were prepared by the melt blending method. The structures and morphologies of (nano)composites were characterized by X‐ray diffraction and TEM. The flammability properties and thermal stability were studied using TGA, cone calorimeter, limiting oxygen index (LOI), and the UL94 protocol. The basal spacing of organo‐LDH increases to 3.89 nm from 0.76 nm in pristine LDH. When 10% of the organo‐LDH was melt blended with PP, the basal spacing of the LDH increases to 4.01 nm. The onset temperature and thermal decomposition temperature of the PP/organo‐LDH and PP/organo‐LDH/zinc borate (nano)composites have no significant change compared to pristine PP, but the amount of non‐volatile residue remaining at 600°C is significantly higher than that in pure PP. The cone calorimetric results show a 38% reduction in the peak heat release rate for PP/10%BZn and 48, 50 and 63% reductions for PP/organo‐LDH/10%BZn (nano)composites at 3, 5 and 10% organo‐LDH loading. The limiting oxygen indices of all samples increase by a slight amount and all samples can obtain a UL‐94 HB rating. The char content of PP/LDH/BZn and PP/BZn/organo‐LDH (nano)composites is much greater than that of PP/LDH, PP/BZn and PP/organo‐LDH. Copyright © 2011 John Wiley & Sons, Ltd.
Aberrantly expressed AURKC enhances the transformation and tumourigenicity of epithelial cells
Authors: Tsou Jen‐Hui , Chang Kung‐Chao , Chang‐Liao Pey‐Yi , Yang Shu‐Ting , Lee Chung‐Ta , Chen Ya‐Ping , Lee Yi‐Chao , Lin Bo‐Wen , Lee Jenq‐Chang , Shen Meng‐Ru , Chuang Chin‐Kai , Chang Wen‐Chang , Wang Ju‐Ming , Hung Liang‐Yi
Published: May 2011

Over‐expression of AURKC has been detected in human colorectal cancers, thyroid carcinoma and several cancer cell lines. However, the regulation and clinical implications of over‐expressed AURKC in cancer cells are unclear. Here we show that elevated AURKC increases the proliferation, transformation and migration of cancer cells. Importantly, the kinase activity of AURKC is required for these tumour‐associated properties. Analysis of human cancer specimens shows that the expression of AURKC is increased in cervical cancer, and is highly correlated with staging in colorectal cancer. Over‐expressed AURKC‐GFP localizes to the centromeric regions of mitotic chromosomes and results in a decreased level of AURKB, a key regulator of spindle checkpoint. Expression of AURKC is down‐regulated by PLZF, a transcriptional repressor, through recruitment to its promoter region. The expression levels of PLZF and AURKC mRNA display opposite patterns in human cervical and colorectal cancers. Taken together, our results provide important insights into human cancers with AURKC expression, which may serve as a potential target for cancer therapy in the future. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Neurobehavioral side effects of corticosteroids during active treatment for acute lymphoblastic leukemia in children are age‐dependent: Report from Dana‐Farber Cancer Institute ALL Consortium Protocol 00‐01
Authors: Mrakotsky Christine M. , Silverman Lewis B. , Dahlberg Suzanne E. , Alyman M. Cheryl A. , Sands Stephen A. , Queally Jennifer T. , Miller Tamara P. , Cranston Amy , Neuberg Donna S. , Sallan Stephen E. , Waber Deborah P.
Published: May 2011

Background

Although corticosteroids remain a mainstay of treatment for acute lymphoblastic leukemia (ALL), they can cause troublesome neurobehavioral changes during active treatment, especially in young children. We evaluated acute neurobehavioral side effects of corticosteroid therapy in preschool versus school‐age children by obtaining structured reports weekly for 1 month.

Procedure

Parents of 62 children (2–17 years) treated on Dana‐Farber Cancer Institute (DFCI) ALL Consortium Protocol 00‐01 participated during the continuation phase of treatment. Patients received cyclical twice‐daily 5‐day courses of prednisone (PRED; 40 mg/m2/day) or dexamethasone (DEX; 6 mg/m2/day). Parents completed behavior rating scales about their child weekly during one steroid cycle [baseline (Day 0), active steroid (Day 7), post‐steroid (Days 14 and 21)].

Results

Behavioral side effects increased significantly (P < 0.001) during the steroid week for preschool children (<6 years) on measures of emotional control, mood, behavior regulation, and executive functions, returning to baseline during the two “off‐steroid” weeks. In contrast, school‐age children (≥6 years) did not demonstrate an increase in side effects during the steroid week. Steroid type (PRED vs. DEX) was not a significant predictor of neurobehavioral side effects.

Conclusions

Preschool children are at greater risk for neurobehavioral side effects during active steroid treatment for ALL than school‐age children and adolescents. DEX was not associated with more neurobehavioral side effects than PRED. Counseling of families about side‐effects should be adapted according to age. The observed effects, moreover, were transient, reducing concerns about longer‐term neurobehavioral toxicities. Pediatr Blood Cancer 2011; 57: 492–498. © 2011 Wiley‐Liss, Inc.
Functionalization of parylene during its chemical vapor deposition
Authors: Naddaka Maria , Asen Florian , Freza Sylwia , Bobrowski Maciej , Skurski Piotr , Laux Edith , Charmet Jerome , Keppner Herbert , Bauer Monika , Lellouche Jean‐Paul
Published: May 2011

Two possible mechanisms for the reaction of four halogenated (metha)acrylate‐based molecules with Parylene [poly (paraxylylene)] during its chemical vapor deposition were proposed. The chemical reactivity of acrylate double bond with the paraxylylene biradical was calculated for all four (metha)acrylate‐based molecules. These calculations allowed the evaluation of the energetically favorable mechanism and indeed a direct correlation was found between both predicted and experimental reactivities. Next, the reactivity of the (metha)acrylate‐modified Parylene films was evaluated through their reaction with different amines. The obtained amidated Parylene films were characterized with X‐ray photoelectron spectroscopy, Kaiser test for primary amines, and fluorescence microscopy. The strong reactivity of (metha)acrylate‐modified Parylene films toward nucleophilic substitution emphasizes a general method for the functionalization of self‐supported Parylene films grown on the reacting solutions using the novel solid on liquid deposition process. This paves the way to the development of multifunctional materials in a one‐step process resulting from the deposition Parylene over liquid patterns. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Mechanistic insight of photo‐induced aggregation of chicken egg white lysozyme: The interplay between hydrophobic interactions and formation of intermolecular disulfide bonds
Authors: Xie Jinbing , Qin Meng , Cao Yi , Wang Wei
Published: May 2011

Recently, it was reported that ultraviolet (UV) illumination could trigger the unfolding of proteins by disrupting the buried disulfide bonds. However, the consequence of such unfolding has not been adequately evaluated. Here, we report that unfolded chicken egg white lysozyme (CEWL) triggered by UV illumination can form uniform globular aggregates as confirmed by dynamic light scattering, atomic force microscopy, and transmission electron microscopy. The assembling process of such aggregates was also monitored by several other methods, such as circular dichroism, fluorescence spectroscopy, mass spectrometry based on chymotrypsin digestion, ANS‐binding assay, Ellman essay, and SDS‐PAGE. Our finding is that due to the dissociation of the native disulfide bonds by UV illumination, CEWL undergoes drastic conformational changes resulting in the exposure of some hydrophobic residues and free thiols. Subsequently, these partially unfolded molecules self‐assemble into small granules driven by intermolecular hydrophobic interaction. With longer UV illumination or longer incubation time, these granules can further self‐assemble into larger globular aggregates. The combined effects from both the hydrophobic interaction and the formation of intermolecular disulfide bonds dominate this process. Additionally, similar aggregation behavior can also be found in other three typical disulfide‐bonded proteins, that is, α‐lactalbumin, RNase A, and bovine serum albumin. Thus, we propose that such aggregation behavior might be a general mechanism for some disulfide‐bonded proteins under UV irradiation. Proteins 2011; © 2011 Wiley‐Liss, Inc.
NMR structure and dynamics of recombinant wild type and mutated jerdostatin, a selective inhibitor of integrin α1β1
Authors: Carbajo Rodrigo J. , Sanz Libia , Mosulén Silvia , Pérez Alicia , Marcinkiewicz Cezary , Pineda‐Lucena Antonio , Calvete Juan J
Published: May 2011

NMR analysis of four recombinant jerdostatin molecules was assessed to define the structural basis of two naturally occurring gain‐of‐function events: C‐terminal dipeptide processing and mutation of the active residue K21 to arginine. Removal of the highly mobile and a bulky C‐terminal dipeptide produced pronounced chemical shift changes in the sequentially unconnected but spatially nearby α1β1 inhibitory loop. Analysis of chemical shift divergence and 15N backbone relaxation dynamics indicated differences in motions in the picosecond to nanosecond time scale, and the higher T2 rate of S25, S26, and H27 of rJerK21 point to a slowdown in the microsecond to millisecond motions of these residues when compared with rJerR21. The evidence presented in this article converges on the hypothesis that dynamic differences between the α1β1 recognition loops of rJerR21 and rJerK21 may influence the thermodynamics of their receptor recognition and binding. A decrease in the μs‐ms time scale may impair the binding affinity by reducing the rate of possible conformations that the rJerK21 can adopt in this time scale. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Lithographically structured biological recognition structures for immunosensing and single cell analytics
Authors: Köhler Oliver , Kowalewski Philipp , Ziegler Christiane
Published: May 2011

The preparation of structured antibody layers was shown. For this purpose, a (3‐aminopropyl)‐trimethoxysilane (APTMS) monolayer on a silicon wafer was pholithographically structured. To the APTMS structures, IgG antibodies can easily be attached via glutaraldehyde coupling. To prevent unspecific bonding to the bare silicon substrate, a commercial blocking agent has to be used.
Force spectroscopy with BSA functionalized cantilevers on TiO2 nanoparticles
Authors: Schäfer Jens , Marxer Elena Eva Julianne , Bakowsky Udo
Published: May 2011

The contact of nanoparticle surfaces with biomolecules often results in interactions. Proteins as one of the most important biomolecules adsorb on nanoparticle surfaces and can affect the way of recognition or of uptake in the cell. Even inhaled nanoparticles can be found on the luminal side of airways and alveoli, major lung tissue compartment or cells and within capillaries. They cross the cell membrane not by endocytotic processes, but by diffusion or adhesive interactions. Due to the possible interaction after inhalative exposure of inorganic nanoparticles with blood biomolecules we investigated the adhesion properties between different TiO2 nanoparticles and commercial silicon or BSA (as a model protein) modified cantilevers with atomic force microscopy (AFM). The characterization of the nanoparticles was done using laser doppler electrophoresis (LDE), dynamic light scattering (DLS) and transmission electron microscopy (TEM) for zeta potential and size. AFM was used to perform force measurements with unmodified tips and BSA functionalized tips. Adhesion measurements showed differences between the inorganic nanoparticles, regarding their ability to interact with the major serum compound BSA.

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Scheme of the adhesion measurements on TiO2 nanoparticles performed with unmodified and BSA modified cantilevers.
Poly(acrylic acid)‐graft‐poly(ethylene glycol) preparation and adsorption on polyelectrolyte multilayers (PEMs) for custom‐made antiadhesive surfaces
Authors: Schmolke Hannah , Hartwig Sven , Klages Claus‐Peter
Published: May 2011

In this study, we report on a simple and versatile method for PEGylation of surfaces which is applicable practically independent of the substrate material: a poly(acrylic acid)‐graft‐poly(ethylene glycol) (PAA‐g‐PEG) copolymer was synthesized with grafting ratios g in the range of g = 20–2 [acrylic acid (AA) monomers to PEG side chains] and adsorbed either on bare stainless steel or on stainless steel precoated with different types of polyelectrolyte multilayers (PEMs) from aqueous solution. For PAA‐g‐PEG synthesis two principal routes were compared with respect to yield and control of g: the active ester route using different carbodiimide coupling agents and the route via poly(acrylic acid chloride) (PAA‐Cl).

Measurements based on Fourier transform infrared spectroscopy in attenuated total reflection mode (FTIR‐ATR) showed that the adsorbed amount of PAA‐g‐PEG copolymer is in general drastically enhanced, compared to bare stainless steel as a substrate, when a suitable PEM is used as an interlayer. The amount was also found to be strongly dependent on the type of PEM and to increase with increasing thickness of the PEM interlayer. The stability of highly PEGylated PEMs and the influence of thermal crosslinking on stability were investigated by immersing the PEM‐PEG samples for 1 week into 1 M NaCl solution at pH 4.5 and 0.15 M phosphate buffered saline (PBS) at pH 7.4, respectively.
GaInN quantum well design and measurement conditions affecting the emission energy S‐shape
Authors: Netzel Carsten , Hatami Soheil , Hoffmann Veit , Wernicke Tim , Knauer Arne , Kneissl Michael , Weyers Markus
Published: May 2011

Polarization fields and charge carrier localization are the dominant factors defining the radiative recombination processes in the quantum wells of most AlGaInN‐based optoelectronic devices. Both factors determine emission energy, emission line width, recombination times, and internal quantum efficiency. For a deeper understanding of the charge carrier recombination processes, we have performed temperature and excitation power dependent photoluminescence experiments on epitaxially grown GaInN structures to study the S‐shape of the temperature dependent emission energy.

The S‐shape behaviour in GaInN quantum wells (QWs) is dominated by the temperature dependence of the charge carrier localization. However, in polar QWs it is strongly affected by the charge carrier density which screens the piezoelectric field. External applied fields change the observable S‐shape characteristic significantly. Semi‐ and nonpolar GaInN QWs feature an S‐shape behaviour which points to much stronger charge carrier localization compared to polar QWs. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tuning of photonic bandgap via dimensional control of nano‐pillars
Authors: Li K. H. , Choi H. W.
Published: May 2011

We report on the fabrication and optical characterization of ordered hexagonal arrays of non‐closed‐packed GaN nano‐pillars formed by nanosphere lithography. A self‐assembled two‐dimensional monolayer of silica nanosphere mask was coated by the technique of spin‐coating. A silica‐selective dry etch recipe was employed to adjust the diameters of the nanospheres. With the dimension‐adjusted nanospheres as an etch mask, the pattern was transferred to a wafer to form a photonic crystal structure. The photonic bandgap structures were designed using Plane Wave Expansion algorithm for bandgap computations. The existence and positions of bandgaps have been verified through angular resolved reflectivity measurement, which correlated well with prediction of simulations. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Dependence of InN properties on MOCVD growth parameters
Authors: Tuna Ö. , Behmenburg H. , Giesen C. , Kalisch H. , Jansen R. H. , Yablonskii G. P. , Heuken M.
Published: May 2011

In order to optimize the growth conditions, the effect of the most important growth parameters such as growth temperature, pressure and V/III ratio on MOCVD‐grown InN was investigated. A series of samples were grown by changing the growth temperature from 500 °C to 550 °C at fixed growth pressure of 800 mbar and V/III ratio of 145000. An improvement of electrical properties with temperature increment was noted. The highest mobility of 1200 cm2/Vs was achieved at 550 °C with a bulk carrier concentration of 4.32 x 1018 cm‐3. The effect of V/III ratio on In droplet formation and on carrier concentration was also studied. At fixed temperature of 520 °C, reactor pressure of 200 mbar and at fixed NH3 flow of 3 slm, a rising TMIn flow from 1.2 µmol/min to 2.0 µmol/min results in a carrier concentration increment from 6.06 x 1018 cm‐3 to 1.33 x 1019 cm‐3and a decrement of the mobility from 430 cm2/Vs to 348 cm2/Vs. X‐ray diffraction measurements show that the intensity associated with In droplets on the surface is rising with increasing TMIn flow. The effect of reactor pressure on InN growth was also examined. A high sensitivity to growth pressure for crystalline quality of InN was observed. The full width at half maximum (FWHM) values of InN (0002) reflexes decreased with increasing reactor pressure. With increasing growth pressure above 200 mbar, FWHM of around 275 arcsec of InN (0002) was achieved. This FWHM value is the lowest reported in literature for MOCVD‐grown InN so far. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Plasmon enhanced optical recording in As‐Se layers
Authors: Charnovych Stepan , Kokenyesi Sandor
Published: May 2011

Here we demonstrate a plasmon enhanced optical recording in As‐Se layers, which are among the most applicable for processing with He‐Ne or other red light emitting lasers. Gold nanoparticles deposited on the silica glass substrate and covered by an amorphous chalcogenide layer satisfy the conditions of efficient surface plasmon resonance in this spectral region. The enhancement of photo‐induced transformations results in an increased rates of photo‐darkening, followed by bleaching and localized volume changes. These experimental results support the importance of localized electric fields in photo‐structural transformations of chalcogenide glasses as well as suggest new approaches for improving the performance of these recording media. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical characterization of sol‐gel‐derived SnO2:Eu nanopowders annealed at high temperatures
Authors: Kiisk Valter , Kangur Triin , Paalo Madis , Tätte Tanel , Pikker Siim , Sildos Ilmo
Published: May 2011

Nanoparticulate SnO2 powders doped with europium (0.5 at%) were prepared by using sol‐gel method. The samples were sintered in air or argon at temperatures ranging from 600 to 1400 °C. Raman‐, SEM‐ and photoluminescence characterization of the samples was carried out. The heat‐treated samples exposed mainly broad emission bands typical of Eu3+ ions in disordered surrounding when excited at 464 nm (direct excitation of Eu3+) whereas spectrally well‐resolved emission characteristic of Eu3+ in crystalline phase was obtained when excited at 266 nm (attributed to host‐sensitization). The broad emission bands quite abruptly disappeared after annealing at 1400 °C. Inert gas (argon) atmosphere was found to improve the emission intensity compared to similar heat treatment in air. It is argued that the observed luminescence behaviour might be explained by the combined effect of the OH groups and the peculiarities of coarsening of the nanopowder induced by heat treatment. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)