bluuebunny/crossref_metadata_2025 huggingface dataset:
Incidence and mortality in epithelial ovarian cancer by family history of any cancer
Authors: Hemminki Kari , Sundquist Jan , Brandt Andreas
Published: March 2011

BACKGROUND:

Practically all data on familial risk in ovarian and other cancers are based on incident cancer, whereas familiality in cancer mortality is largely unknown. If fatal forms of cancer are a highly familial subtype, then familial risk for mortality may exceed that of incidence, which is relevant for clinical decision making and counseling.

METHODS:

Ovarian cancer patients in the nationwide Swedish Family Cancer Database were classified according to fatal and nonfatal (incident) family history. Familial risks for incident and fatal ovarian cancer were calculated for offspring based on their parental or sibling family history of any cancer using standardized incidence ratios (SIRs) for incidence and standardized mortality ratios (SMRs) for mortality. Offspring without family history were referents.

RESULTS:

The database included 24,757 mothers and 8138 daughters with ovarian cancer. When a mother had ovarian cancer, the SIR for incident ovarian cancer in daughters was 2.69, and when a sister had ovarian cancer it was 3.49. The SMRs for fatal cancer by fatal cancer in probands were 3.39 and 5.80, respectively. For fatal serous cancers among siblings, the SMR was 6.16, compared with 10.01 for the endometrioid type. Ovarian cancer was associated with maternal (SIR, 1.22; SMR, 1.56) and sororal breast cancer (SIR, 1.27). Another discordant association was between ovarian and paternal prostate cancer (SIR, 1.12; SMR, 1.66).

CONCLUSIONS:

Fatal familial risks were higher for concordant ovarian, ovarian‐breast, and ovarian‐prostate cancers than the corresponding incident risks. This may suggest that highly fatal subtypes exist for these cancers, calling for genetic dissection. Cancer 2011. © 2011 American Cancer Society.
Effect of Surface Modification on Semiconductor Nanocrystal Fluorescence Lifetime
Authors: Ruedas‐Rama Maria J. , Orte Angel , Hall Elizabeth A. H. , Alvarez‐Pez Jose M. , Talavera Eva M.
Published: March 2011

Semiconductor nanocrystals, namely, quantum dots (QDs), present a set of unique photoluminescence properties, which has led to increased interest in using them as advantageous alternatives to conventional organic dyes. Many applications of QDs involve surface modification to enhance the solubility or biocompatibility of the QDs. One of the least exploited properties of QDs is the very long photoluminescence lifetime that usually has complex kinetics owing to the effect of quantum confinement. Herein, we describe the effect of different surface modifications on the photoluminescence decay kinetics of QDs. The different surface modifications were carefully chosen to provide lipophilic or water‐soluble QDs with either positive or negative surface net charges. We also survey the effect on the QD lifetime of several ligands that interact with the QD surface, such as organic chromophores or fluorescent proteins. The results obtained demonstrate that time‐resolved fluorescence is a useful tool for QD‐based sensing to set the basis for the development of time‐resolved‐based nanosensors.
From tert‐Butylhydrazine Adducts of AlR3 (R = Me, CMe3) to Oligonuclear AlN Cage Compounds – Evidence for a Hydrazine Twist Across an Al3 Triangle
Authors: Uhl Werner , Hagemeier Elke , Layh Marcus , Rezaeirad Babak , Kösters Jutta , Würthwein Ernst‐Ulrich , Ghavtadze Nugzar , Massa Werner
Published: March 2011

The thermal decomposition of the hydrazine adducts R3Al←NH2–N(H)CMe3 (1a, R = CMe3; 1b, R = Me) was investigated. Compound 1a afforded the hydrazide [(Me3C)2Al–N(H)–N(H)–CMe3]2 (2) upon heating to 155 °C. Compound 2 is dimeric in the solid state with a four‐membered Al2N2 heterocycle in its molecular core. Heating of 2 to 190 °C gave the drum‐like imidoalane [Me3CAlNH]6 (4) in which the Al and N atoms occupy the vertices of a hexagonal prism. This reaction is believed to proceed via the dimeric amide [(Me3C)2Al–NH2]2 (3) that was isolated in small quantities from a mixture obtained at a slightly lower temperature. Adduct 1b, which is sterically less shielded than 1a, decomposes readily at room temperature to yield an unprecedented Al–N cage compound, [Me2Al–N(H)–N(H)CMe3]2[MeAl–N(CMe3)–NH] (5), with a norbornane‐like arrangement of three Al and four N atoms, and a hydrazinediido group in the bridging position. Heating of 5 gave, with the release of methane, the tetraaluminum compound [MeAlN(H)–NCMe3]4 (6) in which four hydrazinediide moieties are bridged by AlMe groups. Heating of 6 resulted in the gradual degradation of the N–N bonds and the formal release of 1 or 3 equiv. of nitrene, N–H, to give the unique cage compounds (MeAl)4[N(H)–NCMe3]3(NCMe3) (7) and (MeAl)4[N(H)–NCMe3](NCMe3)3 (8). The structures of compounds 6–8 may be derived from Al4N4 cubes in which a number of edges (four, three or one) are bridged by nitrogen atoms of hydrazinediido groups.
Site‐Selective Arylation of Alizarin and Purpurin Based on Suzuki–Miyaura Cross‐Coupling Reactions
Authors: Mahal Ahmed , Villinger Alexander , Langer Peter
Published: March 2011

A variety of arylated anthraquinones were prepared by site‐selective Suzuki–Miyaura cross‐coupling reactions of the bis‐ and tris(triflates) of alizarin and purpurin, respectively. The site‐selectivity is controlled by the electronic influence of the carbonyl group and by steric parameters.
Efficient Tandem Morita–Baylis–Hillman/Double Cross‐Aldol Reaction between Cyclic Enones and Formaldehyde Promoted by N‐Methylpyrrolidine
Authors: Guerra Krassimira P. , Afonso Carlos A. M.
Published: March 2011

The Lewis base N‐methylpyrrolidine acts in water as an efficient promoter of tandem reactions between 2 cyclopenten‐1‐one and aqueous formaldehyde. The reaction pathway includes, as consecutive independent steps, a MBH reaction and a double cross‐aldol reaction to furnish the new 2,5,5‐tris(hydroxymethyl)‐2‐cyclopenten‐1‐one in excellent yield. A range of cyclic enones and 4‐nitrobenzaldehyde undergo the tandem reaction similarly. The reaction mechanism was also investigated.
Synthesis and Photophysical Properties of Alkynylated Pyrimidines by Site‐Selective Sonogashira Reactions of 2,4,5,6‐Tetrachloropyrimidine; First Synthesis of Tetraalkynyl‐pyrimidines
Authors: Malik Imran , Ahmed Zeeshan , Reimann Sebastian , Ali Iftikhar , Villinger Alexander , Langer Peter
Published: March 2011

A variety of novel alkynyl‐substituted pyrimidines were prepared by the first site‐selective Sonogashira cross‐coupling reactions of 2,4,5,6‐tetrachloropyrimidine. The products, di‐, tri‐, and tetraalkynyl‐pyrimidines, exhibit fluorescence in the range of 395–470 nm. The synthesis of tetraalkynyl‐pyrimidines has not been previously reported, nor has the synthesis of chlorinated di‐ and trialkynylated pyrimidines.
Efficient Access to C1‐ and C3‐Functionalized Isoquinolines: Towards Potential Lanthanide Ligands
Authors: Caillé Fabien , Buron Frédéric , Tóth Éva , Suzenet Franck
Published: March 2011

Highly substituted isoquinolines have been synthesized by two different pathways using either a Pictet–Grams or a Bischler–Napieralski approach. While the first synthesis afforded C1‐functionalizable 1,3‐dimethylisoquinoline derivatives, the second approach allowed the isolation of isoquinoline derivatives bearing a reactive ester function at the challenging C3 position. Among the large variety of efficient chemistry that can be independently or simultaneously performed at the C1 and C3 positions of the isoquinoline ring, 1,3‐dibromomethylisoquinoline derivatives have proven to be efficient intermediates for the synthesis of highly valuable ligands for lanthanide complexation.
Biphasic Voltammetry of N,N,N′,N′‐Tetraphenyl‐para‐phenylenediamine Microdroplets, Microparticles and Microparticle Suspensions
Authors: Halls Jonathan E. , Wadhawan Jay D.
Published: March 2011

The aqueous biphasic voltammetry of the title compound is examined when it is immobilised on an electrode surface either when dissolved in an array of nitrobenzene droplets, in the form of solid microparticles, or when an electrode is immersed into a three‐dimensional aqueous suspension of the solid. In each case, a different electrode reaction is observed to occur, even though the supporting electrolyte is unchanged, with either counter ion transfer across a liquid | liquid interface, or with electrochemical dissolution of the solid particles, or a suggested diffusive‐type electron hopping between individual redox centres embedded within the solid crystals.
Determination of Chemical Oxygen Demand Based on Novel Photoelectro‐bifunctional Electrodes
Authors: Qu Xiao , Tian Min , Chen Shuai , Liao Baoqiang , Chen Aicheng
Published: March 2011

A novel photoelectro‐bifunctional electrode (TiO2/Ti/TiO2‐Pt) for the rapid determination of chemical oxygen demand (COD) has been developed. The TiO2 nanotubes, serving as the photocatalyst and the support of the electrocatalyst, were directly grown on both sides of a Ti plate by anodic oxidation. Pt nanoparticles were loaded on one side of TiO2 nanotubes by the photoreduction method. For the COD determination, the bifunctional electrode exhibits a low detection limit (9.5 mg/L), high sensitivity of 3.55×10−3 mA/(mg/L COD) and high Cl− tolerance (1400 mg/L). When used for the test of real wastewater samples, the results were in excellent agreement with those determined by the standard K2Cr2O7 method.
Effects of ionic strength, temperature and conformation on affinity interactions of β2‐glycoprotein I monitored by capillary electrophoresis
Authors: Bohlin Maria E. , Blomberg Lars G. , Heegaard Niels H. H.
Published: March 2011

We have used CE to evaluate the interaction between β2‐glycoprotein I (β2gpI) and heparin. β2gpI is a human plasma protein involved in the blood coagulation cascade. It is of interest to functionally characterize the interactions of β2gpI because the exact function is not entirely known and because circulating autoantibodies against β2gpI are associated with an increased risk of thrombotic events. The effect of the ionic strength, temperature, and conformation of the protein on the interaction between β2gpI and heparin has been studied. The CE procedure for this study is simple, fast, and automatic. β2gpI and heparin were allowed to interact during electrophoresis at different ionic strength buffers and at different capillary temperatures. To mimic perturbation of the conformation of β2gpI, different denaturing agents (SDS, ACN, and urea) were added to the BGE. While simple 1:1 binding isotherms were obtained at 22°C, the data strongly suggest that at physiological temperature the binding stoichiometry is not 1:1 and/or that cooperative interactions begin to play a role. We found that (i) theKD‐values differed by a factor of 60 at the ionic strengths studied (ii) β2gpI was resistant to denaturation with SDS and ACN, but was partially denatured by urea, and (iii) theKDfor the β2gpI–heparin interaction in the presence of urea was ten times higher than theKDdetermined at the same conditions without urea added. Therefore, we conclude that the interaction between β2gpI and heparin is dependent on electrostatic interactions and on the conformation of β2gpI.
Reduction of protein concentration range difference followed by multicolumn fractionation prior to 2‐DE and LC‐MS/MS profiling of serum proteins
Authors: Selvaraju Subhashini , El Rassi Ziad
Published: March 2011

This article is concerned with the reduction of protein concentration range differences by the peptide beads library technology (ProteoMiner™ or “equalizer” technology), which in principle allows the enrichment of proteins to the same concentration level (i.e. protein equalizer) regardless of the original protein abundance in a given biological fluid such as human serum, which is the subject of our investigation. After the equalization step, the captured proteins from human serum were fractionated on a series of tandem monolithic columns with surface‐bound iminodiacetic acid ligands to which three different metal ions, namely, Zn2+, Ni2+ and Cu2+ were immobilized to yield the so‐called immobilized metal affinity chromatography columns. These three monolithic columns were connected to a reversed‐phase column packed with polystyrene divinyl benzene beads. Aliquots taken from the four collected fractions from the four tandem columns were subsequently fractionated by 2‐DE. Also, aliquots from the four collected fractions were tryptically digested and analyzed by LC‐MS/MS. The strategy of subsequent fractionation on the four tandem columns after equalization allowed the identification of more proteins than simply using the equalization by ProteoMiner™. The equalizer technology was compared to the immuno‐subtraction approach. While the ProteoMiner™ technology is superior in terms of the overall number of captured proteins, it only complements the immuno‐subtraction approach since the latter can capture the proteins that were not captured by the former.
Development of a CE‐ESI‐microTOF‐MS method for a rapid identification of phenolic compounds in buckwheat
Authors: Verardo Vito , Gomez‐Caravaca Ana Maria , Segura‐Carretero Antonio , Caboni Maria Fiorenza , Fernández‐Gutiérrez Alberto
Published: March 2011

A sensitive CE‐ESI‐MS analytical method for the identification of buckwheat antioxidants has been developed. CE and ESI‐TOF parameters (e.g. buffer composition and pH, sheath liquid composition, sheath liquid and gas flow rates, electrospray voltage) were optimized to obtain an optimal analytical separation and identification. The results confirmed the presence of phenolic acids, procyanidins and galloylated propelargonidins. The identification of swertiamacroside and 2‐hydroxy‐3‐O‐β‐D‐glucopyranosil‐benzoic acid, found for the first time in our previous work, has been confirmed. Furthermore, 5,7,4′‐trimethoxyflavan and dihydroxy‐trimethoxyisoflavan have also been tentatively identified for the first time in buckwheat.
Detection and treatment of post stroke depression: results from the registry of the Canadian stroke network
Authors: Herrmann Nathan , Seitz Dallas , Fischer Hadas , Saposnik Gustavo , Calzavara Andrew , Anderson Geoff , Rochon Paula
Published: March 2011

Background

Depression occurs in approximately one‐third of patients following stroke based on studies that screen entire stroke populations. Less is known about the detection and treatment of post stroke depression (PSD) in routine clinical practice.

Methods

This was a prospective cohort study of 7643 consecutive stroke patients >66 years of age, from 13 designated stroke centres in Ontario, Canada. PSD was defined as (a) presence of strong evidence of depression documented in the patient chart plus a prescribed antidepressant and a psychiatric consult, or (b) prescription of a new antidepressant following admission. The prevalence of PSD was determined and patients with and without PSD were compared on a variety of measures. Patients admitted to specialized stroke units were compared to patients admitted to standard units in order to determine if PSD detection and treatment rates differed.

Results

PSD was diagnosed in 4.8%, and 6.7% were treated with a new antidepressant. Patients with PSD had more severe strokes, more functional handicap, longer hospital stays and were less likely to be discharged home (all p < 0.001). Patients admitted to specialized stroke units were more likely to be diagnosed with depression (5.2% vs 4.0%, p < 0.014) and were more likely to receive a new prescription for an antidepressant (7.8% vs 4.5%; p < 0.001).

Conclusions

Rates of diagnosed and treated PSD in routine clinical practice are low and appear significantly lower than those from studies that utilize active screening of entire stroke populations. These results support the routine screening of all patients for PSD using validated instruments. Specialized stroke unit care may improve PSD detection and treatment rates. Copyright © 2011 John Wiley & Sons, Ltd.
Influence of personality on caregiver's burden, depression and distress related to the BPSD
Authors: Melo Graça , Maroco João , de Mendonça Alexandre
Published: March 2011

Objective

We hypothesize that the personality influences the caregiver's depression, burden and distress related to BPSD.

Subjects and methods

Participants were 105 consecutive patients with dementia and their family caregivers, living at home, attending a Dementia Clinic. A cross‐sectional design was used with an applied a structured interview at home. Comprehensive assessments included: personality (NEO‐FFI), burden (ZBI), depression (CES‐D) and distress related to BPSD (NPI‐distress). Statistical Path analysis was used to study the hypothetical causal and mediating effects between independent and criterion variables.

Results

Neuroticism increased, whereas extraversion decreased, both caregiver's depression and burden. Agreeableness was also found to decrease the burden. The personality characteristics only indirectly influenced the caregiver's distress related to BPSD.

Conclusion

These results reinforce the importance of including personality as an individual resource of the caregiver in the conceptual models and research on caregiving. Assessment of caregiver's personality characteristics should be taken into account for the planning of intervention programs. Copyright © 2011 John Wiley & Sons, Ltd.
Pathologic criteria for nonalcoholic steatohepatitis: Interprotocol agreement and ability to predict liver-related mortality
Authors: Younossi Zobair M. , Stepanova Maria , Rafiq Nila , Makhlouf Hala , Younoszai Zahra , Agrawal Ritambhara , Goodman Zachary
Published: March 2011

Since the initial description of nonalcoholic steatohepatitis (NASH), several sets of pathologic criteria for its diagnosis have been proposed. However, their interprotocol agreement and ability to predict long-term liver-related mortality (LRM) have not been demonstrated. In this study, we examined patients with biopsy-proven nonalcoholic fatty liver disease (NAFLD) for whom liver biopsy slides and clinical and mortality data were available. Liver biopsy samples were evaluated for a number of pathologic features and were classified according to the presence or absence of NASH by (1) the original criteria for NAFLD subtypes, (2) the nonalcoholic fatty liver disease activity score (NAS), (3) the Brunt criteria, and (4) the current study's criteria. All NASH diagnostic criteria and individual pathologic features were tested for agreement and for their independent associations with LRM, which were determined with a Cox proportional hazards model. Two hundred fifty-seven NAFLD patients with complete data were included. The diagnoses of NASH by the original NAFLD subtypes and by the current study's definition of NASH were in almost perfect agreement (κ = 0.896). However, their agreement was moderate with NAS (κ = 0.470 and κ = 0.511, respectively) and only fair to moderate with the Brunt criteria (κ = 0.365 and κ = 0.441, respectively). Furthermore, the agreement of the Brunt criteria with NAS was relatively poor (κ = 0.178). During the follow-up (median = 146 months), 31% of the patients died (9% were LRM). After we controlled for confounders, a diagnosis of NASH by the original criteria for NAFLD subtypes [adjusted hazard ratio = 9.94 (95% confidence interval = 1.28–77.08)] demonstrated the best independent association with LRM. Among the individual pathologic features, advanced fibrosis showed the best independent association with LRM [adjusted hazard ratio = 5.68 (95% confidence interval = 1.50–21.45)]. Conclusion: The original criteria for NAFLD subtypes and the current study's criteria for NASH were in almost perfect agreement, but their level of agreement with the NAS and Brunt criteria was lower. A diagnosis of NASH by the original criteria for NAFLD subtypes demonstrated the best predictability for LRM in NAFLD patients. (HEPATOLOGY 2011;)
Hepatic autophagy mediates endoplasmic reticulum stress–induced degradation of misfolded apolipoprotein B
Authors: Qiu Wei , Zhang Jing , Dekker Mark J. , Wang Huajin , Huang Ju , Brumell John H. , Adeli Khosrow
Published: March 2011

Induction of endoplasmic reticulum (ER) stress was previously shown to impair hepatic apolipoprotein B100 (apoB) production by enhancing cotranslational and posttranslational degradation of newly synthesized apoB. Here, we report the involvement of autophagy in ER stress–induced degradation of apoB and provide evidence for a significant role of autophagy in regulating apoB biogenesis in primary hepatocyte systems. Induction of ER stress following short-term glucosamine treatment of McA-RH7777 cells resulted in significantly increased colocalization of apoB with green fluorescent protein–microtubule-associated protein 1 light chain 3 (GFP-LC3), referred to as apoB-GFP-LC3 puncta, in a dose-dependent manner. Colocalization with this autophagic marker correlated positively with the reduction in newly synthesized apoB100. Treatment of McA-RH7777 cells with 4-phenyl butyric acid, a chemical ER stress inhibitor, prevented glucosamine- and tunicamycin-induced increases in GRP78 and phosphorylated eIF2α, rescued newly synthesized [35S]-labeled apoB100, and substantially blocked the colocalization of apoB with GFP-LC3. Autophagic apoB degradation was also observed in primary rat and hamster hepatocytes at basal conditions as well as upon the induction of ER stress. In contrast, this pathway was inactive in HepG2 cells under ER stress conditions, unless proteasomal degradation was blocked with

N

-acetyl-leucinyl-leucinyl-norleucinal and the medium was supplemented with oleate. Transient transfection of McA-RH7777 cells with a wild-type protein kinase R–like ER kinase (PERK) complementary DNA resulted in dramatic induction of apoB autophagy. In contrast, transfection with a kinase inactive mutant PERK gave rise to reduced apoB autophagy, suggesting that apoB autophagy may occur via a PERK signaling–dependent mechanism.

Conclusion:

Taken together, these data suggest that induction of ER stress leads to markedly enhanced apoB autophagy in a PERK-dependent pathway, which can be blocked with the chemical chaperone 4-phenyl butyric acid. ApoB autophagy rather than proteasomal degradation may be a more pertinent physiological mechanism regulating hepatic lipoprotein production in primary hepatocytes. (Hepatology 2011;)
Parenchymal expression of CD40 exacerbates adenovirus-induced hepatitis in mice
Authors: Yan Jiabin , Jie Zuliang , Hou Lifei , Wanderley Joao L. , Soong Lynn , Gupta Shalini , Qiu Suimin , Chan Tehsheng , Sun Jiaren
Published: March 2011

The healthy adult human liver expresses low levels of major histocompatibility complex class II (MHC II) and undetectable levels of immune costimulatory molecules. However, high levels of MHC II, CD40, and B7 family molecules are expressed in the activated Kupffer cells and hepatocytes of patients with viral hepatitis. The precise role of these molecules in viral clearance and immune-mediated liver injury is not well understood. We hypothesized that parenchymal CD40 expression enhances T cell recruitment and effector functions, which may facilitate viral clearance and alleviate liver injury. To test this hypothesis, we generated novel liver-specific, conditional CD40 transgenic mice, and we challenged them intravenously with a recombinant replication-deficient adenovirus carrying Cre recombinase (AdCre). Wild-type mice infected with AdCre developed a relatively mild course of viral hepatitis and recovered spontaneously. CD40 expression in the livers of transgenic animals, however, resulted in CD80 and CD86 expression. The dysregulation of population dynamics and effector functions of intrahepatic lymphocytes (IHLs) resulted in severe lymphocytic infiltration, apoptosis, necroinflammation, and serum alanine aminotransferase elevations in a dose-dependent fashion. To our surprise, an early expansion and subsequent contraction of IHLs (especially CD8+ and natural killer cells), accompanied by increased granzyme B and interferon-γ production, did not lead to faster viral clearance in CD40 transgenic mice.

Conclusion:

Our results demonstrate that hepatic CD40 expression does not accelerate adenoviral clearance but rather exacerbates liver injury. This study unveils a previously unknown deleterious effect of hepatic CD40 on adenovirus-induced liver inflammation. (Hepatology 2011;)
Steps in prostate cancer progression that lead to bone metastasis
Authors: Jin Jung‐Kang , Dayyani Farshid , Gallick Gary E.
Published: March 2011

Prostate cancer is a complex disease in which metastasis to the bone is the main cause of death. Initial stages of metastasis are generally similar to those for most solid tumors; however, the mechanisms that underlie the homing of prostate tumor cells to the bone are not completely understood. Prostate cancer bone metastasis is also a microenvironment‐driven disease, involving bidirectional interactions between the tumor and the bone microenvironment. In this review, we discuss the current understanding of the biologic processes and regulatory factors involved in the metastasis of prostate cancer cells, and their specific properties that promote growth in bone. Although many of these processes still need to be fully elucidated, a better understanding of the complex tumor/microenvironment interplay is slowly leading to more effective therapies for patients with prostate cancer bone metastases.
General aspects of Hertzian potentials modeling in integrated optics
Authors: Massaro Alessandro , Cingolani Roberto
Published: March 2011

This work introduces a novel time‐domain numerical simulator of integrated optical waveguides. Only solutions of two scalar Helmholtz‐equations are used in the evaluation of electric and magnetic Hertzian‐potentials that yields the electromagnetic field in the time domain, and the frequency response by the discrete Fourier transform. All the field components are obtained directly from the scalar potentials, and are not interrelated as in finite‐difference time domain method. The Hertzian potential method (HPM) considers the field‐perturbation effect in proximity of the dielectric discontinuities by generators modeling and takes into account the numerical error of a wave that travels in a dielectric multilayered optical guide. We present in this work the general finite difference discretization and the numerical setting of the HPM related to optical waveguide full‐wave modeling. Copyright © 2011 John Wiley & Sons, Ltd.
Development of a static and exhaustive extraction procedure for field passive preconcentration of chlorophenols in environmental waters with hollow fiber‐supported liquid membrane
Authors: Feng Ying‐Di , Tan Zhi‐Qiang , Liu Jing‐Fu
Published: March 2011

A static and exhaustive extraction mode of hollow fiber‐supported liquid membrane was developed for field sample passive pretreatment of environmental water samples. The extraction device was prepared by immobilizing dihexyl ether in the wall of a polypropylene hollow fiber membrane (60 cm length, 50 μm wall thickness, and 280 μm id) as liquid membrane and filling the fiber lumen with 0.1 M NaOH as acceptor, and closing the two ends of the fiber with an aluminum foil. Passive extraction was conducted by immersing the device into 15 mL water samples modified with 0.01 M HCl and 20% m/v NaCl. Model analytes including 4‐chlorophenol, 2,4‐dichlorophenol, and 2,4,6‐trichlorophenol were transferred into acceptor with extraction efficiencies over 79% in 10 h at room temperature, and determined by high‐performance liquid chromatography. The proposed method has the enrichment factor of 394–498 and LOD of 0.3–0.4 μg/L for the three chlorophenols. Humic acid and salinity in the environmentally relevant range had no significant influence on the extraction, and chlorophenols in various environmental waters were determined with spike recoveries between 71.6 and 120%. The static passive extraction nature benefited field sample pretreatment without power, whereas the exhaustive extraction mode effectively eliminated the sample matrix effects.
Production of Continuous Electrospun Mats with Improved Mechanical Properties
Authors: dos Santos A. M. , Dierck J. , Troch M. , Podevijn M. , Schacht E.
Published: March 2011

A new concept of top‐down electrospinning is described. A dedicated apparatus was designed including the adaptation of a movable needle system in combination with a thin conveyor belt made of an insulation material on the top of the grounded collector plate. The new design, termed ‘needle printing’, permits to electrospin mats with increased size, homogeneous and controllable thicknesses. Due to the increase of bending instability and to the ‘needle printing’, the produced fibres are more regular in shape, longer and are deposited more stretched. In contrast to traditional electrospinning, the fibre population is the same in all regions of the mats imparting the same morphological and mechanical properties to each point of the produced structures.

magnified image
Accelerated cardiac T2 mapping using breath‐hold multiecho fast spin‐echo pulse sequence with k‐t FOCUSS
Authors: Feng Li , Otazo Ricardo , Jung Hong , Jensen Jens H. , Ye Jong C. , Sodickson Daniel K. , Kim Daniel
Published: March 2011

Cardiac T2 mapping is a promising method for quantitative assessment of myocardial edema and iron overload. We have developed a new multiecho fast spin echo (ME‐FSE) pulse sequence for breath‐hold T2 mapping with acceptable spatial resolution. We propose to further accelerate this new ME‐FSE pulse sequence using k‐t focal underdetermined system solver adapted with a framework that uses both compressed sensing and parallel imaging (e.g., sensitivity encoding) to achieve higher spatial resolution. We imaged 12 control subjects in midventricular short‐axis planes and compared the accuracy of T2 measurements obtained using ME‐FSE with generalized autocalibrating partially parallel acquisitions and ME‐FSE with k‐t focal underdetermined system solver. For image reconstruction, we used a bootstrapping two‐step approach, where in the first step fast Fourier transform was used as the sparsifying transform and in the final step principal component analysis was used as the sparsifying transform. When compared with T2 measurements obtained using generalized autocalibrating partially parallel acquisitions, T2 measurements obtained using k‐t focal underdetermined system solver were in excellent agreement (mean difference = 0.04 msec; upper/lower 95% limits of agreement were 2.26/−2.19 msec, respectively). The proposed accelerated ME‐FSE pulse sequence with k‐t focal underdetermined system solver is a promising investigational method for rapid T2 measurement of the heart with relatively high spatial resolution (1.7 × 1.7 mm2). Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Anatomical, blood oxygenation level‐dependent, and blood flow MRI of nonhuman primate (baboon) retina
Authors: Zhang Yi , Wey Hsiao‐Ying , Nateras Oscar San Emeterio , Peng Qi , De La Garza Bryan H. , Duong Timothy Q.
Published: March 2011

The goal of this study was to demonstrate high‐resolution anatomical, blood oxygenation level‐dependent, and blood flow MRI on large nonhuman primate retinas using a 3‐Tesla clinical scanner as a first step toward translation. Baboon was chosen because of its evolutionary similarity to human. Anesthetized preparation, free of eye‐movement artifacts, was used to evaluate clinical scanner hardware feasibility and optimize multimodal protocols for retinal MRI. Anatomical MRI (0.1 × 0.2 × 2.0 mm3) before contrast‐agent injection detected three alternating bright–dark–bright layers. The hyperintense inner strip nearest to the vitreous was enhanced by an intravascular contrast agent, which likely included the ganglion and bipolar cell layer and the embedded retinal vessels. The hypointense middle strip showed no contrast enhancement, which likely included the avascular outer unclear layer and photoreceptor segments. The hyperintense outer strip showed contrast enhancement, which likely corresponded to the choroid vascular layer. In the posterior retina, the total thickness including the choroid was 617 ± 101 μm (± standard deviation, n = 7). Blood oxygenation level‐dependent functional MRI (0.3 × 0.6 × 2.0 mm3) of oxygen inhalation relative to air increased the signals by 6.5 ± 1.4%. Basal blood flow (2 × 2 × 2 mm3) was 83 ± 30 mL/100 g/min (air), and hypercapnia increased blood flow by 25 ± 9% (P < 0.05). This study demonstrates multimodal MRI to image anatomy, physiology, and function on large nonhuman primate retinas using a clinical scanner, offering encouraging data to explore human applications. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
Ultrashort TE MR imaging of bovine cortical bone: The effect of water loss on the T1 and T2* relaxation times
Authors: Kokabi Nima , Bae Won , Diaz Eric , Chung Christine B. , Bydder Graeme M. , Du Jiang
Published: March 2011

The effects of water loss on the T1 and T2* of bovine cortical bone were investigated using ultrashort echo time sequences with signals excited either by a short hard pulse or by two longer half pulses. Nine bovine femur samples were prepared and sequentially air‐ and oven‐dried. On average 3.42% of bone by weight was lost after air‐drying for 3 days, with another 5.98% of bone weight loss after oven‐drying at 100°C for 24 h. T1 and T2* were measured after every 1% decrease in weight, with 9–10% bone weight loss at the termination of the drying process. After both forms of drying, the overall T1 decreased 33% from 153 ± 18 ms to 102 ± 17 ms when measured using the hard pulse and from 186 ± 25 ms to 122 ± 23 ms when using the half pulses. T2* decreased by 45–50% from 368 ± 29 μs to 201 ± 19 μs using the hard pulse and from 379 ± 35 μs to 191 ± 17 μs using the half pulses. A steady decrease of 26–31% was observed in both T1 and T2* with the first 3–4% bone water loss after air‐drying. Oven‐drying at 100°C for 24 h resulted on an additional 4% T1 reduction but 25% T2* reduction. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.
On the performance of strain smoothing for quadratic and enriched finite element approximations (XFEM/GFEM/PUFEM)
Authors: Bordas Stéphane P. A. , Natarajan Sundararajan , Kerfriden Pierre , Augarde Charles Edward , Mahapatra D. Roy , Rabczuk Timon , Pont Stefano Dal
Published: March 2011

By using the strain smoothing technique proposed by Chen et al. (Comput. Mech. 2000; 25:137–156) for meshless methods in the context of the finite element method (FEM), Liu et al. (Comput. Mech. 2007; 39(6):859–877) developed the Smoothed FEM (SFEM). Although the SFEM is not yet well understood mathematically, numerical experiments point to potentially useful features of this particularly simple modification of the FEM. To date, the SFEM has only been investigated for bilinear and Wachspress approximations and is limited to linear reproducing conditions. The goal of this paper is to extend the strain smoothing to higher order elements and to investigate numerically in which condition strain smoothing is beneficial to accuracy and convergence of enriched finite element approximations. We focus on three widely used enrichment schemes, namely: (a) weak discontinuities; (b) strong discontinuities; (c) near‐tip linear elastic fracture mechanics functions. The main conclusion is that strain smoothing in enriched approximation is only beneficial when the enrichment functions are polynomial (cases (a) and (b)), but that non‐polynomial enrichment of type (c) lead to inferior methods compared to the standard enriched FEM (e.g. XFEM). Copyright © 2011 John Wiley & Sons, Ltd.
Telezentriefehler und Telezentriebereich
Authors: Schuster Norbert , Weber Simone
Published: March 2011

Der Vorzug des telezentrischen Strahlengangs zur Erhöhung der Messgenauigkeit ist allgemein bekannt [1]. Oft aber wird in der Bildverarbeitungspraxis nach dem Telezentriebereich gefragt. Dafür wünscht man sich die Angabe eines Intervalls entlang der optischen Achse, innerhalb dessen die Bildverarbeitungsanlage „fehlerfrei”︁ misst. Ausgehend vom Telezentriefehler des Messobjektivs und vom Schärfentiefenbereich bei der Bildaufnahme durch die elektronische Kamera werden die Einflüsse quantifiziert, die den Telezentriebereich festlegen.
How to Perform a Security Check without Undressing People
Authors: May Torsten , Meyer Hans‐Georg
Published: March 2011

People have a desire for security, especially when they are about to enter an aircraft. Nobody wants to sit next to a terrorist flying 30,000 ft above ground. So, modern technology is expected to provide a solution to screen anybody willing to enter an aircraft for hidden threats. Obviously the actual solution using metal detectors and manual control is secure only to a certain level; moreover it is inefficient and offending. Security screening and respecting privacy at the same time constitute a conflict which cannot be easily solved. Characteristic for that dilemma is the actual public discussion regarding the so called “strip scanner” [1], where a technology with high security standard obviously violates privacy when in a figurative sense it undresses people and even worse illuminates them with arguable radiation (x‐ray or millimetre waves). This article describes a possible solution, which respects people's privacy and complies with their basic need for security.
Fs‐Lasers for Life Sciences
Authors: Hellerer Thomas
Published: March 2011

Femtosecond lasers had an unpredictable success in optical sciences ever since they were introduced. Today physicists are still pushing the limits of ultrafast lasers, e.g. the pulse duration down to a single optical cycle and the peak power up to tera or even peta watts. On the other hand, many promising applications have emerged outside the laser laboratories. Mainly the combination of high peak power and low average power make ultrafast lasers very attractive for life sciences. The high peak power enables scientists to take advantage of nonlinear effects while the low average power keeps the cell samples vital/alive. Therefore, it is now possible to gather new information about dynamic life processes that was not accessible before. The studies cover scales reaching from interaction of subcellular compartments up to the physiological reaction of an entire living organism. Some keywords of these applications are “non‐invasive”, “high 3D‐resolution”, “time‐resolved”, “marker‐free”, “contact‐free” and “high penetration depth” among many others.
Ultrafast Laser Oscillators in the Thin Disk Geometry
Authors: Keller Ursula , Südmeyer Thomas
Published: March 2011

One of the major technology trends in laser research is the progress of ultrafast laser sources from complicated laboratory systems towards compact and reliable instruments. SESAM­modelocked ultrafast lasers using the thin disk geometry are a promising technology for this task.
Microscope Technology and Biomedical Applications: A Fit?
Authors: Kempe Michael , Zimmermann Bernhard , Wolleschensky Ralf
Published: March 2011

Biomedical research is increasingly targeting more than just the cell as the classical object of microscopy. On one side of the application spectrum investigations move towards the basic molecular interactions and on the other side large complex systems as model organisms are studied. Both directions and the exploration of function rather than structure provide challenges for the microscopic imaging techniques that — as direct observation methods — are and will remain extremely valuable enabling tools in modern biomedical research.
Blue Laser Diodes
Authors: Piprek Joachim
Published: March 2011

The first demonstration of a GaN‐based blue laser diode by Shuji Nakamura [1] was followed by a tremendous research and development effort around the world. Gallium nitride technology enables a range of novel applications with vast consumer markets. Examples are full‐color video displays, solid‐state lighting, and high‐definition DVD players. However, there still remains a strong need for a more detailed understanding of microscopic physical processes in nitride devices. Advanced models and numerical simulation can help to investigate those processes and to improve the device performance. This article reviews practical examples of GaN‐laser simulation, analysis, and optimization [2, 3].
Investigation of photo‐oxidative effect on morphology and degradation of mechanical and physical properties of nano CaCO3 silicone rubber composites
Authors: Mishra Satyendra , Shimpi Navinchandra G , Mali Ananda D
Published: March 2011

Photo‐oxidative degradation of treated and untreated nano CaCO3: silicone rubber composite was studied under accelerated UV irradiation (≥290 nm) at different time intervals. Prolonged exposure to UV leads to a progressive decrease in mechanical and physical properties along with the change in behavior of filler‐matrix interaction. This was due to decrease in cross‐linking density with increase in mobility of rubber chains. Meanwhile, synthesized nano CaCO3 was modified with stearic acid for uniform dispersion in rubber matrix. The increase in carbonyl (>CO), hydroxyl (OH), CO2, and alkene functional groups on the UV exposed surface of treated and untreated nano CaCO3: silicone rubber composites at different time intervals was studied using Fourier transform infrared (FTIR) spectroscopy. The change in morphological behavior of filler‐matrix interaction after UV exposure was studied using SEM. Overall, the study showed that the treated nano CaCO3: silicone composites were affected more by UV exposure than untreated nano CaCO3: silicone composites and pristine composite after UV exposure. This effect was due to peeling of stearic acid from the surface of CaCO3, which makes the rubber chains slippery and thus separation of filler and rubber chains takes place with initiation of fast‐degradation. Copyright © 2011 John Wiley & Sons, Ltd.
Role of GLI2 in the growth of human osteosarcoma
Authors: Nagao Hiroko , Ijiri Kosei , Hirotsu Masataka , Ishidou Yasuhiro , Yamamoto Takuya , Nagano Satoshi , Takizawa Takumi , Nakashima Kinichi , Komiya Setsuro , Setoguchi Takao
Published: March 2011

The Hedgehog pathway functions as an organizer in embryonic development. Aberrant activation of the Hedgehog pathway has been reported in various types of malignant tumours. The GLI2 transcription factor is a key mediator of Hedgehog pathway but its contribution to neoplasia is poorly understood. To establish the role of GLI2 in osteosarcoma, we examined its expression by real‐time PCR using biopsy tissues. To examine the function of GLI2, we evaluated the growth of osteosarcoma cells and their cell cycle after GLI2 knockdown. To study the effect of GLI2 activation, we examined mesenchymal stem cell growth and the cell cycle after forced expression of GLI2. We found that GLI2 was aberrantly over‐expressed in human osteosarcoma biopsy specimens. GLI2 knockdown by RNA interferences prevented osteosarcoma growth and anchorage‐independent growth. Knockdown of GLI2 promoted the arrest of osteosarcoma cells in G1 phase and was accompanied by reduced protein expression of the cell cycle accelerators cyclin D1, SKP2 and phosphorylated Rb. On the other hand, knockdown of GLI2 increased the expression of p21cip1. In addition, over‐expression of GLI2 promoted mesenchymal stem cell proliferation and accelerated their cell cycle progression. Finally, evaluation of mouse xenograft models showed that GLI2 knockdown inhibited the growth of osteosarcoma in nude mice. Our findings suggest that inhibition of GLI2 may represent an effective therapeutic approach for patients with osteosarcoma. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Mutation of PPP2R1A: a new clue in unveiling the pathogenesis of uterine serous carcinoma
Authors: Shih Ie‐Ming , Wang Tian‐Li
Published: March 2011

Uterine carcinoma is composed mainly of two distinct types: serous and endometrioid. Uterine serous carcinoma, while not as common as endometrioid carcinoma, is a highly aggressive disease and is associated with high mortality. Although the molecular genetic alterations of uterine endometrioid carcinoma have been well established, molecular genetic changes in uterine serous carcinoma are largely unclear. Two recent papers have analysed PPP2R1A mutations among different types of gynaecological neoplasia. Both studies report a surprisingly high frequency of somatic mutations of PPP2R1A in uterine serous carcinomas. PPP2R1A encodes a scaffolding subunit of a major serine/threonine phosphatase, protein phosphatase 2A (PP2A), which plays a critical role in diverse cellular functions, including negative regulation of cellular proliferation and potential tumour suppression. As PPP2R1A is essential for the phosphatase activity of PP2A, this observation should create a new research road map toward elucidating how PPP2R1A mutations and alterations of the PP2A pathway contribute to the pathogenesis of uterine serous carcinoma. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Invited commentary for McConechy M K et al. Subtype‐specific mutation of PPP2R1A in endometrial and ovarian carcinomas. Journal of Pathology. 2011; 223: 567–573. http://dx.doi.org/10.1002/path.2848
First trimester maternal serum PAPP‐A and free β‐HCG levels in hyperemesis gravidarum
Authors: Derbent Aysel Uysal , Yanik Filiz Fatma , Simavli Serap , Atasoy Latife , Ürün Emel , Kuşçu Ülkü Esra , Turhan Nilgün Öztürk
Published: March 2011

Objective

To evaluate whether hyperemesis gravidarum (HG) affects first‐trimester maternal serum PAPP‐A and free β‐hCG levels.

Method

An observational study was conducted in 115 cases of HG and 110 control pregnancies who attended the first‐trimester prenatal screening program between January 2006 and July 2010.

Results

Maternal serum TSH levels were lower and free T4, and transaminases (ALT, AST) levels were higher in pregnancies complicated with HG compared with controls (p < 0.05 for all). In HG cases, median values of maternal serum PAPP‐A were significantly higher with respect to normal pregnancies (1.2 vs 1.0 MoM; p = 0.009). Similarly, median values of free β‐hCG were 1.3 MoM in HG pregnancies and 1.0 MoM in controls (p = 0.006). Multivariate analysis revealed that PAPP‐A and hCG were independently associated with HG after controlling for TSH, free T4, AST, and ALT.

Conclusion

HG is associated with elevated levels of PAPP‐A and free β‐hCG, and such changes are independent of serum indicators of thyroid and liver function. Copyright © 2011 John Wiley & Sons, Ltd.
Evaluation of the antifungal properties of chitosan coating on cut apples using a non‐invasive image analysis technique
Authors: Garrido Assis Odilio B , de Britto Douglas
Published: March 2011

Image analysis techniques have often been chosen as fundamental tools for evaluating the surface and/or structure of organic and inorganic materials over a broad range of scales. In the study reported, a simple image capture system comprising a commercial desktop scanner combined with free image analysis software was used to evaluate the efficiency of antifungal activity of commercial medium‐molecular‐weight chitosan as an edible coating on sliced apples. Fungal growth rate (predominantly Penicillium sp. and Alternaria sp.) was assessed via images acquired twice daily and binary‐transformed for quantitative analysis. The inhibitory effect of chitosan coating on the mycelial fungi growth on cut apple surfaces was confirmed. Chitosan deposited on glass slides was used to simulate film formation and its structure was characterized using atomic force microscopy, revealing a thin porous formation. Copyright © 2011 Society of Chemical Industry