bluuebunny/crossref_metadata_2025 huggingface dataset:
RETRACTED: Sequential loss of cell cycle checkpoint control contributes to malignant transformation of murine embryonic fibroblasts induced by 20‐methylcholanthrene
Authors: Mukherjee Sudeshna , Manna Sugata , Pal Debolina , Mukherjee Pratima , Panda Chinmay K.
Published: March 2010

Definitive information about the number and nature of discrete steps of tumorigenesis is enigmatic. To understand the multistep nature of carcinogenesis, an in vitro model of 20‐Methylcholanthrene‐treated primary fibroblast cells CNCI‐PM‐20, from 20‐day old Swiss mouse embryo was used. Visible neoplastic changes with distinct morphological variations along with specific chromosomal aberrations like Robertsonian metacentrics, double and single‐minute chromosomes and aneuploidy were observed from Passage‐20 onwards. The cell cycle profile showed gradual increase in G2/M population till P‐32, followed by evasion of block from P‐36 onwards. Gradual increase in expression of C‐myc, CyclinD1 and a decrease in expression of P21 was observed from P‐20 onwards. CDC25A expression was significantly increased at P‐27 and remained more or less constant in subsequent passages. Additionally, an increased P16 and P53 expression were seen at P‐20 followed by their significant down‐regulation at P‐32. An increased level of phosphorylated retinoblastoma (ppRb) was observed from P‐27, probably responsible for a compromised G1/S checkpoint. The inactivation of p21 and p16 might be due to their promoter hyper‐methylation as suggested through de‐methylation experiment by 5‐aza‐deoxycytidine at P‐42. G2/M checkpoint abrogation was marked by gradual increase in expression of CyclinB1 and Cdc20, and a significant increase of Mad2 at P‐20. Interestingly, increased expression of phospho‐ATM, ATR and phospho‐Chk1 were also seen at P‐20 followed by their down‐regulation at subsequent passages, indicating a perturbation of DNA damage response pathway at early passages. Our findings therefore dramatize the multiple genetic events that can cooperate to promote tumorigenesis. J. Cell. Physiol. 224:49–58, 2010 © 2010 Wiley‐Liss, Inc.
High glucose regulates cyclin D1/E of human mesenchymal stem cells through TGF‐β1 expression via Ca2+/PKC/MAPKs and PI3K/Akt/mTOR signal pathways
Authors: Ryu Jung Min , Lee Min Young , Yun Seung Pil , Han Ho Jae
Published: March 2010

The elucidation of factors that support human mesenchymal stem cells (hMSCs) growth has remained unresolved partly because of the reliance of many researchers on ill‐defined, proprietary medium formulation. Thus, we investigated the effects of high glucose (D‐glucose, 25 mM) on hMSCs proliferation. High glucose significantly increased [3H]‐thymidine incorporation and cell‐cycle regulatory protein expression levels compared with 5 mM D‐glucose or 25 mM L‐glucose. In addition, high glucose increased transforming growth factor‐β1 (TGF‐β1) mRNA and protein expression levels. High glucose‐induced cell‐cycle regulatory protein expression levels and [3H]‐thymidine incorporation, which were inhibited by TGF‐β1 siRNA transfection and TGF‐β1 neutralizing antibody treatment. High glucose‐induced phosphorylation of protein kinase C (PKC), p44/42 mitogen‐activated protein kinases (MAPKs), p38 MAPK, Akt, and mammalian target of rapamycin (mTOR) in a time‐dependent manner. Pretreatment of PKC inhibitors (staurosporine, 10−6 M; bisindolylmaleimide I, 10−6 M), LY 294002 (PI3 kinase inhibitor, 10−6 M), Akt inhibitor (10−5 M), PD 98059 (p44/42 MAPKs inhibitor, 10−5 M), SB 203580 (p38 MAPK inhibitor, 10−6 M), and rapamycin (mTOR inhibitor, 10−8 M) blocked the high glucose‐induced cellular proliferation and TGF‐β1 protein expression. In conclusion, high glucose stimulated hMSCs proliferation through TGF‐β1 expression via Ca2+/PKC/MAPKs as well as PI3K/Akt/mTOR signal pathways. J. Cell. Physiol. 224:59–70, 2010 © 2010 Wiley‐Liss, Inc.
A role for PKR in hematologic malignancies
Authors: Blalock William L. , Bavelloni Alberto , Piazzi Manuela , Faenza Irene , Cocco Lucio
Published: March 2010

The double‐stranded RNA‐dependent kinase PKR has been described for many years as strictly a pro‐apoptotic kinase. Recent data suggest that the main purpose of this kinase is damage control and repair following stress and, if all else fails, apoptosis. Aberrant activation of PKR has been reported in numerous neurodegenerative diseases and cancer. Although a subset of myelodysplastic syndromes (MDS) and chronic lymphocytic leukemia contain low levels of PKR expression and activity, elevated PKR activity and/or expression have been detected in a wide range of hematologic malignancies, from bone marrow failure disorders to acute leukemia. With the recent findings that cancers containing elevated PKR activity are highly sensitive to PKR inhibition, we explore the role of PKR in hematologic malignancies, signal transduction pathways affected by PKR, and how PKR may contribute to leukemic transformation. J. Cell. Physiol. 223:572–591, 2010. © 2010 Wiley‐Liss, Inc.
Hypoxia induces BMP‐2 expression via ILK, Akt, mTOR, and HIF‐1 pathways in osteoblasts
Authors: Tseng Wen‐Pei , Yang Shu‐Ning , Lai Chih‐Ho , Tang Chih‐Hsin
Published: March 2010

It has been shown that hypoxia stimulation regulates bone formation, maintenance, and repair. Bone morphogenetic protein (BMP) plays important roles in osteoblastic differentiation and bone formation. However, the effects of hypoxia exposure on BMP‐2 expression in cultured osteoblasts are largely unknown. Here we found that hypoxia stimulation increased mRNA and protein levels of BMP‐2 by qPCR, Western blot and ELISA assay in osteoblastic cells MG‐63, hFOB and bone marrow stromal cells M2‐10B4. Integrin‐linked kinase (ILK) inhibitor (KP‐392), Akt inhibitor (1L‐6‐hydroxymethyl‐chiro‐inositol‐2‐[(R)‐2‐O‐methyl‐3‐O‐octadecylcarbonate]) or mammalian target of rapamycin (mTOR) inhibitor (rapamycin) inhibited the potentiating action of hypoxia. Exposure to hypoxia increased the kinase activity of ILK and phosphorylation of Akt and mTOR. Furthermore, hypoxia also increased the stability and activity of HIF‐1 protein. The binding of HIF‐1α to the HRE elements after exposure to hypoxia was measured by EMSA assay. Moreover, the use of pharmacological inhibitors or genetic inhibition revealed that both ILK/Akt and mTOR signaling pathway were potentially required for hypoxia‐induced HIF‐1α activation and subsequent BMP‐2 up‐regulation. Taken together, our results provide evidence that hypoxia enhances BMP‐2 expression in osteoblasts by an HIF‐1α‐dependent mechanism involving the activation of ILK/Akt and mTOR pathways. J. Cell. Physiol. 223:810–818, 2010. © 2010 Wiley‐Liss, Inc.
Involvement of Cx43 phosphorylation in 5′‐N‐ethylcarboxamide‐induced migration and proliferation of mouse embryonic stem cells
Authors: Kim Mi Ok , Lee Yu Jin , Han Ho Jae
Published: March 2010

Despite a lot of gap junction research, the complex connection between gap junction and cell proliferation remains an exciting area of investigation. Thus, we examined the effect of connexin 43 (Cx43) on the migration and proliferation of embryonic stem (ES) cells and its related signaling pathways following stimulation with the adenosine analogue 5′‐N‐ethylcarboxamide (NECA). NECA increased phosphorylation of Cx43 which was blocked by caffeine, a non‐selective adenosine receptor antagonist. In experiment to measure the gap junctional intercellular communication, NECA blocked transfer of Lucifer yellow to neighboring cells in a scrape loading/dye transfer (SL/DT) assay. In addition, NECA‐induced phosphorylation of phosphoinositide 3‐kinase (PI3K)/Akt, protein kinase C (PKC), mitogen‐activated protein kinases (MAPKs), and nuclear factor‐kappa B (NF‐κB) signal pathways. Inhibition of these signaling pathways reduced NECA‐induced phosphorylation of Cx43. Moreover, NECA‐treated cells demonstrated phosphorylation of Src, which was blocked by caffeine. In this experiment, a disruption of Cx43 using Cx43‐specific small interfering RNA (siRNA) also enhanced Src phosphorylation. In a further study, phosphorylations of integrin β1, focal adhesion kinase (FAK), and paxillin by NECA were restrained by caffeine as well as the Src blocker, PP2. Finally, we identified that NECA‐stimulated cell migration and expressions of cell‐cycle regulatory proteins [cyclin D1, cyclin‐dependent kinase (CDK) 4, cyclin E, and CDK2]; these increases were inhibited by caffeine, or PP2. We conclude that NECA‐stimulated Cx43 phosphorylation mediated by PI3K/Akt, PKC, MAPKs, and NF‐κB, which subsequently stimulated cell migration and proliferation through Src, integrin β1, FAK, and paxillin signal pathways. J. Cell. Physiol. 224:187–194, 2010 © 2010 Wiley‐Liss, Inc.
Regulatory factors and cell populations involved in skeletal muscle regeneration
Authors: Ten Broek Roel W. , Grefte Sander , Von den Hoff Johannes W.
Published: March 2010

Skeletal muscle regeneration is a complex process, which is not yet completely understood. Satellite cells, the skeletal muscle stem cells, become activated after trauma, proliferate, and migrate to the site of injury. Depending on the severity of the myotrauma, activated satellite cells form new multinucleated myofibers or fuse to damaged myofibers. The specific microenvironment of the satellite cells, the niche, controls their behavior. The niche contains several components that maintain satellite cells quiescence until they are activated. In addition, a great diversity of stimulatory and inhibitory growth factors such as IGF‐1 and TGF‐β1 regulate their activity. Donor‐derived satellite cells are able to improve muscle regeneration, but their migration through the muscle tissue and across endothelial layers is limited. Less than 1% of their progeny, the myoblasts, survive the first days upon intra‐muscular injection. However, a range of other multipotent muscle‐ and non‐muscle‐derived stem cells are involved in skeletal muscle regeneration. These stem cells can occupy the satellite cell niche and show great potential for the treatment of skeletal muscle injuries and diseases. The aim of this review is to discuss the niche factors, growth factors, and other stem cells, which are involved in skeletal muscle regeneration. Knowledge about the factors regulating satellite cell activity and skeletal muscle regeneration can be used to improve the treatment of muscle injuries and diseases. J. Cell. Physiol. 224:7–16, 2010 © 2010 Wiley‐Liss, Inc.
Cadmium‐induced hormetic effect in differentiated Caco‐2 cells: ERK and p38 activation without cell proliferation stimulation
Authors: Mantha Marc , Jumarie Catherine
Published: March 2010

Cadmium (Cd) is a toxic metal that enters the food chain. Following oral ingestion, the intestinal epithelium may in part protect against Cd toxicity but is also a target tissue. Using human enterocytic‐like Caco‐2 cells, we have previously shown differences in sensitivity to Cd according to the differentiation status. The present study focuses on Cd effects on differentiated cells. Concentration and time‐dependent increases in MTT (3‐[4,5‐dimethyl‐2‐thiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide assay) activity were observed in post‐confluent cultures exclusively, with a twofold maximal stimulation in 21‐day‐old cells exposed to 10 µM Cd for 24 h. No concomitant increase in [methyl‐3H] thymidine incorporation was noted and Cd did not modify cell distribution in the cell‐cycle phases. However, Cd‐induced increase in MTT activity was inhibited by cycloheximine as well as by inhibitors of ERK1/2 and p38, but not by that of JNK. Consistently, Cd increased the levels of ERK1/2 and p38 phosphorylation. Inhibition of Ras‐GTP or PI3K enhanced the stimulatory effect of Cd, whereas mTOR inhibition had no effect. Inhibition of G protein‐phospholipase and PKC decreased MTT stimulation. These results show a hormesis‐like stimulation of Cd on MTT activity in differentiated intestinal cells exclusively. This effect is not related to cell proliferation but more likely to increased protein synthesis which involves ERK1/2 and p38 cascades and possibly PLC‐β signaling pathways. Because growth‐related differentiation of intestinal cells is linked to the selective and sequential activation of MAPKs, the impacts that these Cd‐induced perturbations in signaling pathways may have on intestinal functions clearly deserve to be investigated. J. Cell. Physiol. 224:250–261, 2010 © 2010 Wiley‐Liss, Inc.
Prolonged blockade of VEGF receptors does not damage retinal photoreceptors or ganglion cells
Authors: Miki Akiko , Miki Katsuaki , Ueno Shinji , Wersinger Delphine M. Bonnet , Berlinicke Cynthia , Shaw Gillian C. , Usui Shinichi , Wang Yuxia , Zack Donald J. , Campochiaro Peter A.
Published: March 2010

It has recently been reported that relatively short‐term inhibition of vascular endothelial growth factor (VEGF) signaling can cause photoreceptor cell death, a potentially clinically important finding since VEGF blockade has become an important modality of treatment of ocular neovascularization and macular edema. However, in a set of studies in which we achieved extended and complete blockage of VEGF‐induced vascular leakage through retinal expression of a VEGF binding protein, we did not observe any toxicity to retinal neurons. To follow‐up on these apparently discrepant findings, we designed a set of experiments with the kinase inhibitor SU4312, which blocks phosphorylation of VEGF receptors, to look directly for evidence of VEGF inhibition‐related retinal toxicity. Using transgenic mice with sustained expression of VEGF in photoreceptors, we determined that periocular injection of 3 µg of SU4312 every 5 days markedly suppressed subretinal neovascularization, indicating effective blockade of VEGF signaling. Wild‐type mice given periocular injections of 5 µg of SU4312 every 5 days for up to 12 weeks showed normal scotopic and photopic electroretinograms (ERGs), no TUNEL stained cells in the retina, and no reduction in outer nuclear layer thickness. Incubation of cultured ganglion cells or retinal cultures containing photoreceptors with high doses of SU4312 did not reduce cell viability. These data suggest that blocking VEGF signaling in the retina for up to 12 weeks does not damage photoreceptors nor alter ERG function and should reassure patients who are receiving frequent injections of VEGF antagonists for choroidal and retinal vascular diseases. J. Cell. Physiol. 224:262–272, 2010 © 2010 Wiley‐Liss, Inc.
Comparison of biological reactors (biofilter, biotrickling filter and modified RBC) for treating dichloromethane vapors
Authors: Ravi R. , Philip Ligy , Swaminathan T.
Published: March 2010

BACKGROUND: Bioreactors used for waste gas and odor treatment have gained acceptance in recent years to treat volatile organic compounds (VOCs). Different types of bioreactors (biofilter, biotrickling filter and rotating biological reactor) have been used for waste gas treatment. Most studies reported in the literature have used one of these systems to treat several types of inorganic and organic gases either individually or in mixtures. Each of these reactors has some advantages and some limitations. Though biodegradation is the main process for the removal of pollutants, the mechanisms of removal and the microbial communities may differ among these bioreactors. Consequently their performance or removal efficiency may also be different.

RESULTS: At low loading rate (<35 g m−3 h−1), all three bioreactors showed comparable removal efficiencies and elimination capacity, but at higher loading rates, rotating biological contactors (RBC) showed a better performance with higher removal efficiency (40–50%) than both the biofilter and biotrickling filter (20–40%). The biofilter showed a sharp drop in removal efficiency and elimination capacity at high loading rates.

CONCLUSIONS: The modified RBC had no clogging problems and no increase in pressure drop when compared with the other bioreactors. It can thus handle pollutant load for a longer period of time. This is the first study attempting to compare the performance of three different bioreactors for removal of the same VOC under different conditions. Copyright © 2010 Society of Chemical Industry
Complete ectopia cordis with anencephaly: A case report
Authors: Chopra Seema , Kalpdev Arun , Suri Vanita , Aggarwal Neelam , Rohilla Meenakshi
Published: March 2010

We report a case of pentalogy of Cantrell with anencephaly diagnosed in utero on 2‐dimensional sonography at 17 weeks of gestation. Due to associated anencephaly, termination of pregnancy was carried out. Histopathological examination confirmed the sonographic findings. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound, 2010
Mechanisms of injury to white matter adjacent to a large intraventricular hemorrhage in the preterm brain
Authors: Adler Ira , Batton Dan , Betz Bradford , Bezinque Steven , Ecklund Kirsten , Junewick Joseph , McCauley Roy , Miller Cindy , Seibert Joanna , Specter Barbara , Westra Sjirk , Leviton Alan
Published: March 2010

The purpose of this article is to investigate the hyperechoic lesion seen adjacent to a lateral ventricle that contains blood but is not distended. The literature on ependymal barrier dysfunction was reviewed in search of mechanisms of injury to the white matter adjacent to an intraventricular hemorrhage. The clinical literature on the clinical diagnosis of periventricular hemorrhagic infarction was also reviewed to find out how frequently this diagnosis was made. Support was found for the possibility that the ventricular wall does not always function as an efficient barrier, allowing ventricular contents to gain access to the white matter where they cause damage. Hemorrhagic infarction may not be the only or the most frequent mechanism of white matter damage adjacent to a large intraventricular hemorrhage. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound, 2010
Force spectroscopy as a tool to investigate the properties of supported lipid membranes
Authors: Canale C. , Jacono M. , Diaspro A. , Dante S.
Published: March 2010

Solid supported lipid bilayers (SLB) are extensively used as a model for the investigation of cell membranes in a variety of spectroscopic and biophysical methods. It is nevertheless well known that the interaction with the solid substrate, such as mica or silicon, influences the properties of the membranes. In this article we have employed atomic force microscopy (AFM) in force spectroscopy mode (FS) to investigate the local mechanical properties of lipid membranes supported on mica and on polymer cushion. The lipid double layers were obtained by fusion of unilamellar vesicle of phospholipids. The polymer support was created by self‐assembly of charged polyelectrolytes. Force spectroscopy provided information about the breakthrough force, the breakthrough depth, and the sample adhesion. A batch analysis algorithm to process high‐resolution force mapping was developed. The breakthrough force to indent the bilayers down to the support and the adhesion force were measured as a function of the membrane charge. The comparison of the data obtained from SLB on mica and from bilayers on polymer cushion provides direct evidence about the influence of the substrate on the local mechanic properties of the membrane. As a major result, the yield force distribution of membranes on polymer cushion was bimodal, compared to the unimodal distribution obtained on mica. Microsc. Res. Tech. 73:965–972, 2010. © 2010 Wiley‐Liss, Inc.
Combination of atomic force microscopy and principal component analysis as a general method for direct recognition of functional and structural domains in nanonocomposite materials
Authors: Torre Bruno , Bicego Manuele , Cristiani Marco , Murino Vittorio , Diaspro Alberto , Cingolani Roberto
Published: March 2010

In this work, we report a simple method to direct identify nanometer sized textures in composite materials by means of AFM spectroscopy, aiming at recognizing structured region to be further investigated. It consists in acquiring a set of dynamic data organized in spectroscopy maps and subsequently extracting most valuable information by means of the principal component analysis (PCA) method. This algorithm projects the information of D spectroscopy curves, each containing P data, acquired at each point of an LxC grid into a subset of LxC maps without any assumption on the sample structure, filtering out redundancies and noise. As a consequence, a huge amount of 3D data is condensed into few 2D maps, easy to be examined. Results of this algorithm allow to find and locate regions of interest within the map, allowing a further reduction of data series to be extensively analyzed or modeled. In this work, we explain the main features of the method and show its application on a nanocomposite sample. Microsc. Res. Tech. 73:973–981, 2010. © 2010 Wiley‐Liss, Inc.
AFM measurement of the stiffness of layers of agarose gel patterned with polylysine
Authors: Salerno Marco , Dante Silvia , Patra Niranjan , Diaspro Alberto
Published: March 2010

Films of agarose gel microspotted with polylysine aqueous solution have been characterized by atomic force microscopy carried out in deionized water. Thickness and surface morphology of the layers have been checked, and the effect of polylysine impregnation on the local elasticity has been investigated. An increase in contact stiffness of the organic layer at the spotted areas has been observed, correlated with the polylysine concentration. For the considered agarose layer thickness of ∼0.9 μm in dry condition, the concentration threshold at which stiffening appears is ∼0.1 mg/mL. Above this threshold, the stiffening coefficient becomes approximately twofold and seems not to increase significantly with concentration in the range 0.3–0.7 mg/mL. For concentrations above the stiffening threshold, this effect is also accompanied by a locally lower film thickness. For quantitative determination of the stiffness, force–distance curves extracted from the regions of interest of spots and agarose substrate have been selected and processed. These curves were fitted to the Hertz model of purely elastic tip‐surface interaction, under appropriate assumptions on both tip shape and optimum indentation depth. In this way, we could determine the Young's modulus of the agarose layer to be ∼50 kPa and quantitatively confirm the stiffening due to polylysine. Microsc. Res. Tech. 73:982–990, 2010. © 2010 Wiley‐Liss, Inc.
Unbiased stereological estimation of the rat fetal pituitary volume and of the total number and volume of TSH cells after maternal dexamethasone application
Authors: Manojlović‐Stojanoski Milica , Nestorović Nataša , Ristić Nataša , Trifunović Svetlana , Filipović Branko , Šošić‐Jurjević Branka , Sekulić Milka
Published: March 2010

Glucocorticoids have an inhibitory influence on proliferation activity of the pituitary cells while stimulating apoptosis. Therefore, it was hypothesized that the synthetic glucocorticoid, dexamethasone (DX), has an inhibitory influence on the number of thyroid‐stimulating hormone (TSH) cells during fetal development. The effects of maternal administration of DX on stereological parameters of TSH cells, and TSH serum concentration were investigated in 21‐day‐old rat fetuses. On day 16 of pregnancy, the experimental dams received 1.0 mg DX/kg b.w. subcutaneously, followed by 0.5 mg DX/kg b.w./day on days 17 and 18 of gestation. The control gravid females received the same volume of saline vehicle. TSH cells were stained immunocytochemically by the peroxidase–antiperoxidase (PAP) method. The fetal pituitary volumes were estimated using Cavalieri's principle. A physical disector counting technique in combination with the fractionator sampling method was used for estimation of pituitary TSH cell number. Cell and nuclear volumes were measured with a planar rotator. Maternal DX application was found to cause a significant decrease of pituitary volume and number of TSH cells per pituitary in 21‐day‐old fetuses in comparison with the control fetuses. TSH cell number expressed per body weight unit declined significantly after maternal DX administration. These results indicate an inhibitory DX influence on proliferative activity of precursors and likely differentiated TSH cells and increased apoptotic prevalence. The histological appearance, volume of TSH cells and TSH serum concentration suggest intensive synthetic activity in TSH cells of DX exposed fetuses. Microsc. Res. Tech. 73:1077–1085, 2010. © 2010 Wiley‐Liss, Inc.
Electron microscopy studies of electron‐beam sensitive PbTe‐based nanostructures
Authors: Falqui Andrea , Bertoni Giovanni , Genovese Alessandro , Marras Sergio , Malerba Mario , Franchini Isabella R. , Manna Liberato
Published: March 2010

PbTe nanocrystals were synthesized and then reacted with a toluene solution containing AuCl3. Depending on the reaction conditions and on the starting PbTe nanocrystals morphology, different kinds of nanostructures have been obtained: single defect‐free PbTe nanocrystals with and without an external amourphous oxide shell, crystalline‐Au core/amorphous PbxTeyAuz shell structure, large balloon‐shaped (or mushroom‐shaped) Au domain attached via its apex to the surface of the nanocrystals. Structure and composition of these different types of nanostructure have been studied by means of Cs‐corrected High Resolution Transmission Electron Microscopy (HRTEM) and Scanning Transmission Electron Microscopy (STEM) together with Energy Dispersive X‐Ray Spectrometry (EDX), respectively. These nanostructures have been found sensitive to the high‐intensity electron beam and its effect has been investigated. Microsc. Res. Tech. 73:944–951, 2010. © 2010 Wiley‐Liss, Inc.
Cellular uptake pathway and drug release characteristics of drug‐encapsulated glycol chitosan nanoparticles in live cells
Authors: Park Sangjin , Lee So Jin , Chung Hyunjin , Her Songwook , Choi Yongseok , Kim Kwangmeyung , Choi Kuiwon , Kwon Ick Chan
Published: March 2010

Herein, we evaluated the cellular uptake pathways of hydrophobically modified glycol chitosan (HGC) nanoparticles as nano‐sized drug carriers using cellular imaging technology. The endocytic pathway of nanocarriers for intracellular drug delivery is of great interest for the design of high efficacy delivery carriers for therapeutic agents. To evaluate the cellular uptake pathways of HGC nanoparticles, HGC was chemically labeled with near infrared (NIR) fluorescence dye, Cy5.5, to visualize the nanoparticle under confocal laser scanning microscopy. The internalization pathways of HGC nanoparticles were evaluated after treatment of specific endocytosis inhibitors. Importantly, HCG nanoparticles showed different cellular uptake efficiency and intracellular fate in cytoplasm according to the internalization pathways. Furthermore, drug distribution also evaluated according to the endocytic pathways after treatment of drug encapsulated HGC nanoparticles. As a model drug, fluorescent photosensitizer, Ce6, was encapsulated into HGC (Ce6‐HGC) nanoparticles and the distribution of Ce6 in cytoplasm was evaluated using confocal laser scanning microscopy. The intracellular drug distribution showed different manner through specific endocytic pathways. The cellular imaging technology is highly useful for evaluation of endocytosis pathways and intracellular fate of drug delivery carrier which are closely related to drug distribution and therapeutic efficacy. Microsc. Res. Tech. 73:857–865, 2010. © 2010 Wiley‐Liss, Inc.
Effect of encapsulation or grafting on release kinetics of recombinant human bone morphogenetic protein‐2 from self‐assembled poly(lactide‐co‐glycolide ethylene oxide fumarate) nanoparticles
Authors: Mercado Angel E. , Jabbari Esmaiel
Published: March 2010

The objective of this work was to compare the release characteristics ofRecombinant humanbone morphogenetic protein‐2 (rhBMP‐2) encapsulated in thermally self‐assembled poly(lactide ethylene oxide fumarate) (PLEOF) nanoparticles (NPs) with rhBMP‐2 grafted to succinimide‐terminated poly(lactide fumarate) (PLAF‐NHS) or poly(lactide‐co‐glycolide fumarate) (PLGF‐NHS) NPs. The amphiphilic PLEOF NPs had average size of 110 ± 50 nm. The hydrophobic PLAF‐NHS and PLGF‐NHS NPs had average size of 242 ± 67 and 195 ± 42 nm, respectively. PLEOF NPs had rhBMP‐2 encapsulation efficiency ranging from 65 to 93%. Grafting efficiency of rhBMP‐2 to PLAF‐NHS and PLGF‐NHS NPs was 97% ± 1% and 98% ± 1%, respectively. PLEOF NPs displayed a relatively high‐release rate of rhBMP‐2 in the first week, which rapidly dropped to zero after 10 days. PLEOF NPs grafted with 10 and 20 μg/mL rhBMP‐2 released 67 and 80% of the protein in the active conformation after degradation. PLGF‐NHS NPs displayed sustained release of rhBMP‐2 in the first 2 weeks but dropped to almost zero rate (<3 ng/day) after 20 days. PLAF‐NHS NPs showed the longest period of sustained release of active rhBMP‐2 at two rates: a high rate of 25–35 ng/mL in the first 2 weeks followed by a low rate of 5–10 ng/mL from 2 to 6 weeks. Nearly, 25 and 50% of the rhBMP‐2 released from PLGF‐NHS and PLAF‐NHS NPs, respectively, were enzymatically active after degradation of the NPs. PLEOF NPs provided a fast release of rhBMP‐2 for 1 week, whereas PLAF‐NHS NPs provided a slow release for up to 6 weeks. Microsc. Res. Tech. 73:824–833, 2010. © 2010 Wiley‐Liss, Inc.
Rationalized approach to the determination of contact point in force–distance curves: Application to polymer brushes in salt solutions and in water
Authors: Melzak Kathryn A. , Moreno‐Flores Susana , Yu Kai , Kizhakkedathu Jayachandran , Toca‐Herrera José L.
Published: March 2010

In this work, we present two methods to determine the contact point in force–distance curves obtained with the atomic force microscope. These procedures are compared with the typical determination of contact point by a visual assessment of the data. One method, based on the assumption that the sample shows linear elastic behavior, provides results similar to those obtained by a visual assessment of the data, and will be suitable for determining the contact point in cases where ionic repulsion is not significant. The second method is based on a series of measurements in which the sample deformation is measured at increasing values of applied load; the contact point is determined by extrapolation to zero load. Because this method is based on extrapolation of measurements made in the contact regime, it is not subject to long‐range repulsion. It is thus suitable for the analyses of the contact point even in cases where ionic repulsions will affect the point at which individual force curves deviate from the baseline or zero‐force regime. The methods described here are demonstrated with a glycopolymer brush compressed with a colloidal silica particle on the tip of the AFM cantilever. Microsc. Res. Tech. 73:959–964, 2010. © 2010 Wiley‐Liss, Inc.
Strengthen decision making by asking the right questions
Authors: Cohen Gary B.
Published: March 2010

Many leaders believe it is incumbent on them to make any and every decision they can. Before long, nobody will make a decision without the leader's approval. As a result, the decision‐making process becomes tedious, inefficient, and often ineffective. And morale dips as people on all levels of the organization get frustrated since they aren't being trusted to do challenging and important work. Cohen explains that to combat the speed of change and cascade of information, leaders must direct decisions to the appropriate party. First ask, “Whose decision is it?” and let job descriptions dictate who should decide. Then ask supportive, open‐ended questions that empower and motivate the decision‐maker.
Redefining leadership in the Asia Pacific
Authors: Davis Gerry , Langton Stephen
Published: March 2010

That technology and globalization are rewriting the rules for 21st century business is undisputed. Both have opened rich new veins of products and places where they are sold. Yet the authors report that a leadership crisis is emerging in the Asia Pacific region fuelled by the twin forces of economic expansion and demographics, with the Baby Boomer generation retiring faster than the executive pool can be replaced. The authors examine the challenges posed by these critical trends for both Asian and Western companies.
Dietary energy restriction, in part through glucocorticoid hormones, mediates the impact of 12‐O‐tetradecanoylphorbol‐13‐acetate on jun D and fra‐1 in sencar mouse epidermis
Authors: Przybyszewski Joseph , Wang Weiqun , Au Angela , Perry Courtney , Guetzko Megan , Koehler Ken , Birt Diane F.
Published: March 2010

Dietary energy restriction (DER, 40% calorie reduction from fat and carbohydrate) inhibited mouse skin carcinogenesis and decreased 12‐O‐tetradecanoyl‐13‐phorbol acetate (TPA)‐induced activator protein‐1 (AP‐1):DNA binding previously. This study measured protein levels of c‐jun, jun B, jun D, c‐fos, fra‐1, and fra‐2 and examined their contribution to AP‐1:DNA binding by electrophoretic mobility shift assay (EMSA) with supershift analysis in the epidermis of control and DER Sencar mice exposed to TPA. TPA significantly increased c‐jun, jun B, c‐fos, fra‐1, and fra‐2 and decreased jun D within 3–6 h after treatment. AP‐1:DNA binding reached a maximum 2.5‐fold induction over controls 4 h after TPA treatment and antibodies to jun B, jun D, and fra‐2 in the EMSA binding reaction resulted in supershifts in both acetone‐ and TPA‐treated mice 1–6 h after treatment. The effect of corticosterone (CCS) and DER on the AP‐1 proteins and on the composition of the AP‐1:DNA complex was measured in adrenalectomized (adx) mice. DER reduced the TPA impact on jun D and enhanced the induction of fra‐1. In addition, CCS‐supplemented groups had significantly lower jun D and higher fra‐2 than adx groups and sham groups. While sham animals treated with either acetone or TPA contained jun B, jun D, and fra‐2 proteins in the AP‐1:DNA complex by supershift analysis, fra‐2 was no longer seen in adx DER animals. In summary, our study supports potential roles for jun D, jun B, and fra‐1 in the DER regulation of AP‐1 function in the Sencar mouse skin carcinogenesis model. © 2010 Wiley‐Liss, Inc.
Naturally occurring asteriscunolide A induces apoptosis and activation of mitogen‐activated protein kinase pathway in human tumor cell lines
Authors: Negrín Gledy , Eiroa José L. , Morales Manuel , Triana Jorge , Quintana José , Estévez Francisco
Published: March 2010

Sesquiterpene lactones have attracted much attention because they display a wide range of biological activities, including antitumor properties. Here, we show the effects of the naturally occurring sesquiterpene lactone asteriscunolide A (AS) on viability of human melanoma, leukemia and cells that overexpress antiapoptotic proteins, namely Bcl‐2 and Bcl‐xL. All cell lines were sensitive to this compound, with IC50 values of ∼5 µM. The cytotoxic effects of AS were accompanied by a G2‐M phase arrest of the cell cycle and a concentration‐ and time‐dependent appearance of apoptosis as determined by DNA fragmentation, translocation of phosphatidylserine to the cell surface and sub‐G1 ratio. Apoptosis was associated with caspase‐3 activity and poly(ADP‐ribose) polymerase cleavage and was prevented by the nonspecific caspase inhibitor z‐VAD‐fmk, indicating that caspases are essential components in this pathway. The apoptotic effect of AS was also associated with (i) the release of cytochrome c from mitochondria which was accompanied by dissipation of the mitochondrial membrane potential (ΔΨm) and (ii) the activation of the mitogen‐activated protein kinases (MAPKs) pathway. AS‐induced cell death was potentiated by inhibition of extracellular signal‐regulated kinases (ERK) 1/2 signaling with U0126 and PD98059. Intracellular reactive oxygen species (ROS) seem to play a pivotal role in this process since high levels of ROS were produced early (1 h) and apoptosis was completely blocked by the free radical scavenger N‐acetyl‐L‐cysteine (NAC). The present study demonstrates that AS‐induced cell death is mediated by an intrinsic‐dependent apoptotic event involving mitochondria and MAPKs, and through a mechanism dependent on ROS generation. © 2010 Wiley‐Liss, Inc.
Genetic polymorphisms in DNA repair genes XPC, XPD, and XRCC4, and susceptibility to Helicobacter pylori infection‐related gastric antrum adenocarcinoma in Guangxi population, China
Authors: Long Xi‐Dai , Ma Yun , Huang Yong‐Zhi , Yi Yun , Liang Qiu‐Xiang , Ma Ai‐Min , Zeng Li‐Ping , Fu Guo‐Hui
Published: March 2010

Genetic polymorphisms in DNA repair genes may influence individual variation in DNA repair capacity, which may be associated with risk of gastric antrum adenocarcinoma (GAA) related to Helicobacter pylori infection. This study, including 361 GAAs and 616 controls without any evidence of tumors, was designed to evaluate the association between the polymorphisms of DNA repair genes XPC Ala499Val (RS#2228000) and Lys939Gln (RS#2228001), XPD Lys751Gln (RS#13181), and XRCC4 Ala247Ser (RS#3734091) and Ser298Asn (RS#1805377), and GAA risk for Guangxi population by means of TaqMan‐PCR analysis. Increased risks of GAA were found for individuals with H. pylori positive [odds ratio (OR), 2.48; 95% confidence interval (CI), 1.84–3.33] or cagA positive (OR, 7.34; 95% CI, 5.46–9.87). No differences were observed among the studied groups with regard to the genotype distribution of XPC codons 499 and 939 and of XRCC4 codon 247; but XPD codon 751 genotypes with Gln [ORs (95% CI) were 2.67 (1.98–3.58) and 3.97 (2.64–5.99) for Lys/Gln and Gln/Gln, respectively] and XRCC4 codon 298 genotypes with Asn [ORs (95% CI) were 3.01 (2.21–4.10) and 4.78 (3.24–7.05) for Ser/Asn and Asn/Asn, respectively] increased the risk of GAA. Interestingly, there was an interactive effect between the risk genotypes of these two genes and cagA‐positive status in the GAA risk (ORinteract = 2.05 and 2.08, respectively). However, we did not find the gene–H. pylori‐status interaction effects on the risk of GAA (Pinteract > 0.05). The results suggested that the polymorphisms of XPD codon 751 and XRCC4 codon 298 are associated with an increased risk of developing H. pylori‐related GAA among Guangxi population. © 2010 Wiley‐Liss, Inc.
Self‐efficacy in rheumatoid arthritis: translation and test of validity, reliability and sensitivity of the Danish version of the Rheumatoid Arthritis Self‐Efficacy Questionnaire (RASE)
Authors: Primdahl J. , Wagner L. , Hørslev‐Petersen Kim
Published: March 2010

Objectives: To describe the translation and test of the Danish version of the original British ‘Rheumatoid Arthritis Self‐Efficacy Questionnaire’ (RASE).

Methods: The questionnaire was forward and back translated by individuals with Danish and English as their respective primary languages. The questionnaire was tested by five lay‐people and in the field by 10 + five persons with rheumatoid arthritis (RA). A test‐retest was performed on 62 outpatients with RA. The sensitivity of the adapted Danish version of RASE (RASE‐DK) was finally tested on 106 outpatients with RA – before, immediately after and three months after they had participated in a short self‐management course performed by a multidisciplinary team.

Results: RASE‐DK showed good face validity, but ‘relaxation’ was interpreted in various ways. Internal consistency evaluated by Cronbach's alpha was 0.91. Reliability evaluated by the intra‐class correlation coefficient (ICC) was 0.88. A Bland–Altman plot showed good agreement. RASE‐DK, like the original English version of RASE, was not associated with disease activity (Disease Activity Score, DAS‐28) or disability (Health Assessment Questionnaire, HAQ), and correlated significantly with the Arthritis Self‐Efficacy Scale (ASES) subscales ‘other’ and ‘pain’, and total ASES. RASE‐DK showed a highly significant change, from baseline to immediately after participation in the short course (p < 0.001). The effect faded during the following three months.

Conclusion: RASE‐DK met the appropriate standards for validity, reliability and sensitivity, and is appropriate for use in Denmark. However, the concept of self‐efficacy may be too abstract for a few individuals, and relaxation is interpreted in various ways by the Danish patients. Copyright © 2010 John Wiley & Sons, Ltd.
Current Awareness in NMR in Biomedicine
Authors:   John Wiley & Sons, Ltd.
Published: March 2010

In order to keep subscribers up‐to‐date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of NMR in biomedicine. Each bibliography is divided into 12 sections: 1 Reviews; 2 General; 3 Technology; 4 Contrast Agents; 5 Brain and Nerves; 6 Neuropathology; 7 Cancer; 8 Cardiac, Vascular and Respiratory Systems; 9 Liver, Kidney and Other Organs; 10 Muscle and Orthopaedic; 11 Plants, Micro‐organisms and Parasites; 12 Others. Within each section, articles are listed in alphabetical order with respect to author. If, in the preceding period, no publications are located relevant to any one of these headings, that section will be omitted.
A multiscale finite element method for the dynamic analysis of surface‐dominated nanomaterials
Authors: Park Harold S.
Published: March 2010

The purpose of this article is to present a multiscale finite element method that captures nanoscale surface stress effects on the dynamic mechanical behavior of nanomaterials. The method is based upon arguments from crystal elasticity, i.e. the Cauchy–Born rule, but significantly extends the capability of the standard Cauchy–Born rule by accounting for critical nanoscale surface stress effects, which are well known to have a significant effect on the mechanics of crystalline nanostructures. We present the governing equations of motion including surface stress effects, and demonstrate that the methodology is general and thus enables simulations of both metallic and semiconducting nanostructures. The numerical examples on elastic wave propagation and dynamic tensile and compressive loading show the ability of the proposed approach to capture surface stress effects on the dynamic behavior of both metallic and semiconducting nanowires, and demonstrate the advantages of the proposed approach in studying the deformation of nanostructures at strain rates and time scales that are inaccessible to classical molecular dynamics simulations. Copyright © 2010 John Wiley & Sons, Ltd.
A generalized finite element formulation for arbitrary basis functions: From isogeometric analysis to XFEM
Authors: Benson D. J. , Bazilevs Y. , De Luycker E. , Hsu M.‐C. , Scott M. , Hughes T. J. R. , Belytschko T.
Published: March 2010

Many of the formulations of current research interest, including iosogeometric methods and the extended finite element method, use nontraditional basis functions. Some, such as subdivision surfaces, may not have convenient analytical representations. The concept of an element, if appropriate at all, no longer coincides with the traditional definition. Developing a new software for each new class of basis functions is a large research burden, especially, if the problems involve large deformations, non‐linear materials, and contact. The objective of this paper is to present a method that separates as much as possible the generation and evaluation of the basis functions from the analysis, resulting in a formulation that can be implemented within the traditional structure of a finite element program but that permits the use of arbitrary sets of basis functions that are defined only through the input file. Elements ranging from a traditional linear four‐node tetrahedron through a higher‐order element combining XFEM and isogeometric analysis may be specified entirely through an input file without any additional programming. Examples of this framework to applications with Lagrange elements, isogeometric elements, and XFEM basis functions for fracture are presented. Copyright © 2010 John Wiley & Sons, Ltd.
On the control of the load increments for a proper description of multiple delamination in a domain decomposition framework
Authors: Allix O. , Kerfriden P. , Gosselet P.
Published: March 2010

In quasi‐static non‐linear time‐dependent analysis, the choice of the time discretization is a complex issue. The most basic strategy consists in determining a value of the load increment that ensures the convergence of the solution with respect to time on the base of preliminary simulations. In more advanced applications, the load increments can be controlled for instance by prescribing the number of iterations of the non‐linear resolution procedure, or by using an arc‐length algorithm. These techniques usually introduce a parameter whose correct value is not easy to obtain. In this paper, an alternative procedure is proposed. It is based on the continuous control of the residual of the reference problem over time, whose measure is easy to interpret. This idea is applied in the framework of a multiscale domain decomposition strategy in order to perform 3D delamination analysis. Copyright © 2010 John Wiley & Sons, Ltd.
Post‐thrombotic syndrome after central venous catheter removal in childhood cancer survivors is associated with a history of obstruction
Authors: Revel‐Vilk Shoshana , Menahem Motti , Stoffer Chanie , Weintraub Michael
Published: March 2010

Background

A potential long‐term complication of central venous catheter (CVC)‐related deep vein thrombosis (DVT), both symptomatic and asymptomatic, is development of post‐thrombotic syndrome (PTS) characterized by persistent pain, swelling, and skin changes. Signs and symptoms of PTS were reported after CVC removal. The aim of this study was to assess the risk factors for development of PTS in childhood cancer survivors.

Procedure

Children followed at the after cancer follow‐up clinic were enrolled. The patients were screened for PTS using Kuhle's PTS pediatric score. Patient's records were retrospectively reviewed for clinical and CVC‐related data.

Results

Fifty‐one children were enrolled at a median of 2.3 (range 0.33–7.5) years after removal of their CVC. The median age of the children the time of treatment was 6.5 (range 0.25–18) years. Mild PTS was present in 20 children (39%, 95% CI 26–54%). Pain symptoms were reported in five children (9.5%, 95% CI 3.3–21.4%). Higher rate of PTS was found in children with history of CVC occlusion. The odd ratio (95% CI) for PTS in children with history of occlusion was 3.7 (95% CI 1.1–12.5%) (P = 0.029). The occurrence of PTS was not associated with age at the time of treatment, time from CVC removal, duration of CVC, and history of infection.

Conclusions

Screening cancer survivors for PTS after CVC removal should be integrated to the after cancer follow‐up clinic. Obstruction of CVC may indicate for asymptomatic DVT. Whether thromboprophylaxis and/or prevention of CVC occlusion can decrease the rate of PTS needs to be studied. Pediatr Blood Cancer 2010;55:153–156. © 2010 Wiley‐Liss, Inc.