bluuebunny/crossref_metadata_2025 huggingface dataset:
Acute toxicity of the cationic surfactant C12-benzalkonium in different bioassays: How test design affects bioavailability and effect concentrations
Authors: Chen Yi , Geurts Marc , Sjollema Sascha B. , Kramer Nynke I. , Hermens Joop L.M. , Droge Steven T.J.
Published: November 2013

Using an ion-exchange–based solid-phase microextraction (SPME) method, the freely dissolved concentrations of C12-benzalkonium were measured in different toxicity assays, including 1) immobilization of Daphnia magna in the presence or absence of dissolved humic acid; 2) mortality of Lumbriculus variegatus in the presence or absence of a suspension of Organisation for Economic Co-Operation and Development (OECD) sediment; 3) photosystem II inhibition of green algae Chlorella vulgaris; and 4) viability of in vitro rainbow trout gill cell line (RTgill-W1) in the presence or absence of serum proteins. Furthermore, the loss from chemical adsorption to the different test vessels used in these tests was also determined. The C12-benzalkonium sorption isotherms to the different sorbent phases were established as well. Our results show that the freely dissolved concentration is a better indicator of the actual exposure concentration than the nominal or total concentration in most test assays. Daphnia was the most sensitive species to C12-benzalkonium. The acute Daphnia and Lumbriculus tests both showed no enhanced toxicity from possible ingestion of sorbed C12-benzalkonium in comparison with water-only exposure, which is in accordance with the equilibrium partitioning theory. Moreover, the present study demonstrates that commonly used sorbent phases can strongly affect bioavailability and observed effect concentrations for C12-benzalkonium. Even stronger effects of decreased actual exposure concentrations resulting from sorption to test vessels, cells, and sorbent phases can be expected for more hydrophobic cationic surfactants. Environ Toxicol Chem 2014;33:606–615. © 2013 SETAC
Polychlorinated biphenyl profiles in ringed seals (Pusa Hispida) reveal historical contamination by a military radar station in Labrador, Canada
Authors: Brown Tanya M. , Fisk Aaron T. , Helbing Caren C. , Reimer Ken J.
Published: November 2013

Significant amounts of soil contaminated with polychlorinated biphenyls (PCBs) were discovered at a military radar station in Saglek Bay, Labrador, Canada, in 1996. Subsequent work showed elevated PCB concentrations in local marine sediments, in the benthic-associated food web, and in some ringed seals (Pusa hispida). The benthic-associated food web clearly reflected local PCB contamination, but the high PCB concentrations found in some ringed seals remained unexplained. In the present study, the authors assess the extent to which this local PCB source at Saglek Bay is contributing to the contamination of ringed seals in northern Labrador. Among 63 ringed seals sampled along the northern Labrador coast, 5 (8%) had PCB levels that were higher than recorded anywhere else in the Canadian Arctic. In addition, compared with seals exhibiting a long-range signal, 45% and 60% of subadults and adult males, respectively, exhibited heavier PCB congener profiles as characterized by principal components analysis, >1.6-fold higher PCB/organochlorine pesticides ratios, and higher PCB concentration-weighted average log octanol–water partition coefficient values, consistent with a local source. Despite the spatially confined nature of contaminated sediments in Saglek Bay, the influence of this PCB source is not inconsequential; PCB concentrations in locally contaminated adult males are 2-fold higher than concentrations in those exposed only to long-range PCB sources and exceed an established threshold of 1.3 mg/kg for adverse health effects in seals. Environ Toxicol Chem 2014;33:592–601. © 2013 SETAC
Cellular uptake of nanoparticles as determined by particle properties, experimental conditions, and cell type
Authors: Kettler Katja , Veltman Karin , van de Meent Dik , van Wezel Annemarie , Hendriks A. Jan
Published: November 2013

The increased application of nanoparticles (NPs) is increasing the risk of their release into the environment. Although many toxicity studies have been conducted, the environmental risk is difficult to estimate, because uptake mechanisms are often not determined in toxicity studies. In the present study, the authors review dominant uptake mechanisms of NPs in cells, as well as the effect of NP properties, experimental conditions, and cell type on NP uptake. Knowledge of NP uptake is crucial for risk assessment and is essential to predict the behavior of NPs based on their physical–chemical properties. Important uptake mechanisms for eukaryotic cells are macropinocytosis, receptor-mediated endocytosis, and phagocytosis in specialized mammalian cells. The studies reviewed demonstrate that uptake into nonphagocytic cells depends strongly on NP size, with an uptake optimum at an NP diameter of approximately 50 nm. Increasing surface charges, either positive or negative, have been shown to increase particle uptake in comparison with uncharged NPs. Another important factor is the degree of (homo-) aggregation. Results regarding shape have been ambiguous. Difficulties in the production of NPs, with 1 property changed at a time, call for a full characterization of NP properties. Only then will it be possible to draw conclusions as to which property affected the uptake. Environ Toxicol Chem 2014;33:481–492. © 2013 SETAC
Electrodeposited Palladium Nanoflowers for Electrocatalytic Applications
Authors: Maniam K. K. , Chetty R.
Published: November 2013

Palladium was electrodeposited on an electrochemically activated carbon black substrate using potentiostatic technique, with and without the addition of polyethylene glycol (PEG‐6000) as an additive. Scanning electron micrographs showed change in morphology of Pd from spherical to flower, with increasing additive concentration. As an electrocatalyst for oxygen reduction reaction (ORR), formic acid oxidation and CO stripping, Pd nanoflowers displayed three‐ to fourfold increase in electrocatalytic activity in comparison to the spherical Pd deposits in terms of electrochemical surface area (ESA) and mass specific current density. X‐ray diffraction (XRD) patterns showed, the introduction of additive with varying concentration effect the direction of Pd growth thereby changing the morphology from spherical to flower. The result demonstrates an increase in efficiency of Pd utilization achieved with the addition of PEG during electrodeposition, which could also be applicable to other precious metal electrocatalysts. A scheme for the change in Pd morphology during electrodeposition with additive is also proposed.
Continental margin basins in East Asia: tectonic implications of the Meso‐Cenozoic East China Sea pull‐apart basins
Authors: Suo Y. H. , Li S. Z. , Zhao S. J. , Somerville I. D. , Yu S. , Dai L. M. , Xu L. Q. , Cao X. Z. , Wang P. C.
Published: November 2013

The East China Sea basins, located in the West Pacific Continental Margin (WPCM) since the late Mesozoic, mainly include the East China Sea Shelf Basin (ECSSB) and the Okinawa Trough (OT). The WPCM and its adjacent seas can be tectonically divided into five units from west to east, including the Min‐Zhe Uplift, ECSSB, the Taiwan–Sinzi Belt, OT, and the Ryukyu Island Arc, which record regional tectonic evolution and geodynamics. Among those tectonic units, the ECSSB and the OT are important composite sedimentary pull‐apart basins, which experienced two stages of strike‐slip pull‐apart processes. In seismic profiles, the ECSSB and the OT show a double‐layer architecture with an upper half‐graben overlapping on a lower graben. In planar view, the ECSSB and the OT are characterized by faulted blocks from south to north in the early Cenozoic and by a zonation from west to east in the late Cenozoic. The faulted blocks with planar zonation and two‐layer vertical architecture entirely jumped eastward from the Min‐Zhe Uplift to the OT during the late Cenozoic. In addition, the whole palaeogeomorphology of the ECSSB changed notably, from pre‐Cenozoic highland or mountain into a Late Eocene continental margin with east‐tilting topography caused by the eastward tectonic jumping. The OT opened to develop into a back‐arc basin until the Miocene. Synthetic surface geological studies in the China mainland reveal that the Mesozoic tectonic setting of the WPCM is an Andean‐type continental margin developing many sinistral strike‐slip faults and pull‐apart basins and the Cenozoic tectonic setting of the WPCM is a Japanese‐type continental margin developing dextral strike‐slip faults and pull‐apart basins. Thus, the WPCM underwent a transition from Andean‐type to Japanese‐type continental margins at about 80 Ma (Late Cretaceous) and a transition in topography from a Mesozoic highland to a Cenozoic lowland, and then to below sea‐level basins. Copyright © 2013 John Wiley & Sons, Ltd.
Do changes in specific cognitive functions predict changes in health‐related quality of life in people with Alzheimer's disease?
Authors: Bosboom Pascalle R. , Almeida Osvaldo P.
Published: November 2013

Objective

Currently available pharmacological treatments in Alzheimer's disease (AD) have been associated with modest benefits to cognition, but the impact on health‐related quality of life (HRQoL) is less well established. Our aim was to determine if decline of specific cognitive functions commonly associated with AD predict which patients maintain or experience a deterioration of their HRQoL over 18 months.

Methods

We completed an 18‐month longitudinal study of 47 community‐dwelling older adults diagnosed with probable AD of mild or moderate severity (NINCDS‐ADRD criteria) and their family carers. The primary outcomes of interest were 18‐month change in self‐reported and carer‐reported ratings on the quality of life‐AD (QoL‐AD). The main explanatory variables were 18‐month change in specific cognitive functions using a broad range of established tests. Because of multiple comparisons, alpha was set at 1%.

Results

Twenty six of 47 and 20/47 participants with AD showed evidence of stable or increased QoL‐AD over 18 months according to self report and carer report. Logistic regression analyses showed that for every increase in one standardized score of California Verbal Learning Test‐II short delay free recall the odds of stable/increased self‐rated QoL‐AD over 18 months were 0.27 (95%CI: 0.11, 0.67; p = 0.005). After adjustment for anxiety and depression, this inverse association no longer met the study criteria for statistical significance (adjusted OR: 0.31, 95%CI: 0.11, 0.86; p = 0.025). None of the other standardized changes of cognitive scores were associated with self‐rated or carer‐rated QoL‐AD grouping.

Conclusion

Changes in specific cognitive functions are not associated with changes in HRQoL ratings in AD. Findings suggest that interventions that limit their focus to improving cognitive functions of people with mild to moderate AD living in the community might fail to have an impact on participants' HRQoL. Copyright © 2013 John Wiley & Sons, Ltd.
Asporin and the Mineralization Process in Fluoride-Treated Rats
Authors: Houari Sophia , Wurtz Tilmann , Ferbus Didier , Chateau Danielle , Dessombz Arnaud , Berdal Ariane , Babajko Sylvie
Published: November 2013

Microarray analysis of odontoblastic cells treated with sodium fluoride has identified the asporin gene as a fluoride target. Asporin is a member of the small leucine-rich repeat proteoglycan/protein (SLRP) family that is believed to be important in the mineralization process. In this study, asporin expression and distribution were investigated by systematic analysis of dentin and enamel, with and without fluoride treatment. Specific attention was focused on a major difference between the two mineralized tissues: the presence of a collagenous scaffold in dentin, and its absence in enamel. Normal and fluorotic, continually growing incisors from Wistar rats treated with 2.5 to 7.5 mM sodium fluoride (NaF) were studied by immunochemistry, in situ hybridization, Western blotting, and RT-qPCR. Asporin was continuously expressed in odontoblasts throughout dentin formation as expected. Asporin was also found, for the first time, in dental epithelial cells, particularly in maturation-stage ameloblasts. NaF decreased asporin expression in odontoblasts and enhanced it in ameloblasts, both in vivo and in vitro. The inverse response in the two cell types suggests that the effector, fluoride, is a trigger that elicits a cell-type-specific reaction. Confocal and ultrastructural immunohistochemistry evidenced an association between asporin and type 1 collagen in the pericellular nonmineralized compartments of both bone and dentin. In addition, transmission electron microscopy revealed asporin in the microenvironment of all cells observed. Thus, asporin is produced by collagen-matrix-forming and non-collagen-matrix-forming cells but may have different effects on the mineralization process. A model is proposed that predicts impaired mineral formation associated with the deficiency and excess of asporin. © 2014 American Society for Bone and Mineral Research.
Hemolytic uremic syndrome associated with paraquat intoxication
Authors: Jang Ha Nee , Bae Eun Jin , Hwang Kyungo , Kang Yeojin , Yun Seongeun , Cho Hyun Seop , Chang Se‐Ho , Park Dong Jun
Published: November 2013

We report a case of a 66‐year‐old patient with paraquat intoxication resulting in the requirement for hemoperfusion, hemodialysis, and plasma exchange. His initial serum paraquat level was 0.24 µg/mL (0.0–0.1 µg/mL). Activated charcoal (50 g) was administered orally, and high‐dose N‐acetylcysteine (150 mg/kg) was administered intravenously. In addition, immediate 4 h hemoperfusion was also performed for three consecutive days after admission. Hemodialysis was started on the 4th day after admission because of uremia. On the 9th day after admission, laboratory findings demonstrated hemolytic uremic syndrome (HUS): microangiopathic hemolytic anemia (MAHA), thrombocytopenia, elevated reticulocyte count, and lactate dehydrogenase (LDH). Plasma exchange was performed three times consecutively. Anemia and thrombocytopenia were improved, and LDH was normalized after plasma exchange. Urine output increased to 2240 mL/day on the 18th day after admission, and hemodialysis was discontinued. He is currently being observed at our follow‐up clinic without renal impairment or pulmonary dysfunction for 1.5 years since discharge. We should suspect paraquat‐associated HUS when thrombocytopenia and anemia are maintained for a long time after paraquat intoxication. J. Clin. Apheresis 29:183–186, 2014. © 2013 Wiley Periodicals, Inc.
A multilayered representation, quantum mechanical and molecular mechanics study of the CH3F + OH− reaction in water
Authors: Chen Jie , Xu Yulong , Wang Dunyou
Published: November 2013

The bimolecular nucleophilic substitution (SN2) reaction of CH3F + OH− in aqueous solution was investigated using a combined quantum mechanical and molecular mechanics approach. Reactant complex, transition state, and product complex along the reaction pathway were analyzed in water. The potentials of mean force were calculated using a multilayered representation with the DFT and CCSD(T) level of theory for the reactive region. The obtained free energy activation barrier for this reaction at the CCSD(T)/MM representation is 18.3 kcal/mol which agrees well with the experimental value at ∼21.6 kcal/mol. Both the solvation effect and solute polarization effect play key roles on raising the activation barrier height in aqueous solution, with the former raising the barrier height by 3.1 kcal/mol, the latter 1.5 kcal/mol. © 2013 Wiley Periodicals, Inc.
Charge Density Analysis and Bond Characterization of 3d‐Transition Metal Complexes
Authors: Wang Yu
Published: November 2013

Chemical bond, which makes molecules from independent atoms, is a very important concept in understanding the molecular behavior. Bond characterization is therefore becoming ever needed for predicting the physical and chemical properties of the molecule and the material. Combined experimental and molecular orbital calculation studies have been used for such purpose in terms of deformation density distribution, natural bond orbital analysis and the topological analysis on the total electron density. These analyses provide not only the distribution of density accumulation and density depletion, but also the information such as bond order, bond type etc. Atom domain in molecule or compound can be defined uniquely. Therefore the combined quantum mechanical calculation and high resolution X‐ray crystallography studies will be extremely useful for characterizing the chemical bond precisely. Bonding in 3d‐transition metal complexes is a major topic in coordination chemistry. The complexity of the 3dorbital splittings subjected in the ligand field is well known and this makes the bonding characterization more interesting and challenging. Charge density analysis on a series of Cr compounds, which contain a Cr‐L multiple bond, will be presented. Detail characterization of Cr‐nitrido, ‐oxo, ‐imido, ‐carbyne and ‐carbene bonds will be described. Metal squarates of late 3dtransition elements have been investigated systematically. The valence shell charge concentration (VSCC) around metal ion will be demonstrated by the Laplacian topology, which provides the physical basis for the Lewis structure and valence shell electron pair repulsion (VSEPR). The metal‐metal bond is extremely important for metal clusters; the metal‐metal quintuple bond is rare and a detail analysis will be described. Electronic configurations of the 3dmetal ion play important role in coordination chemistry; taking the advantage of the x‐ray absorption spectroscopy available in synchrotron radiation facility, the exact electronic configuration can be monitored. The great recent improvements on both experiment and theory have made the charge density analysis more accessible to even more complicated system, for example, the excited state or the meta‐stable states.
Efficient and Facile Catalyst‐free One‐Pot Synthesis and Characterization of Some Novel Bis(2‐benzothiazole) Derivatives
Authors: Naeimi Hossein , Tarazian Reza
Published: November 2013

A general method for preparation of benzothiazole derivatives including oxidative cyclization of the corresponding Schiff bases was reported. Herein, we have been synthesized a series of new acyclic‐substituted bis(2‐arylbenzothiazoles). Synthesis of analogs substituted in the benzothiazole ring was achieved via the direct condensation reaction of o‐aminothiophenol with some of dialdehyde compounds under catalyst free in high yields. The structure of these products has been fully characterized by physical and spectroscopic data such as IR, 1H‐NMR, 13C‐NMR, UV‐Vis, MS, and CHN analysis.
Perfusion Imaging
Authors: Günther Matthias
Published: November 2013

MRI has become a reliable tool in medical imaging for assessing morphological and functional details of the human body in a noninvasive manner. Perfusion is an important parameter to assess status and functionality of tissue and organs. This review summarizes the different approaches to measure perfusion based on MRI. Some basics of the theoretical background are provided as well as measurement techniques with and without contrast media are described. J. Magn. Reson. Imaging 2014;40:269–279. © 2013 Wiley Periodicals, Inc.
MR venography of the fetal brain using susceptibility weighted imaging
Authors: Neelavalli Jaladhar , Mody Swati , Yeo Lami , Jella Pavan Kumar , Korzeniewski Steven J. , Saleem Sheena , Katkuri Yashwanth , Bahado‐Singh Ray O. , Hassan Sonia S. , Haacke E. Mark , Romero Roberto , Thomason Moriah E.
Published: November 2013

Purpose

To evaluate the feasibility of performing fetal brain magnetic resonance venography using susceptibility weighted imaging (SWI).

Materials and Methods

After obtaining informed consent, pregnant women in the second and third trimester were imaged using a modified SWI sequence. Fetal SWI acquisition was repeated when fetal or maternal motion was encountered. The median and maximum number of times an SWI sequence was repeated was four and six respectively. All SWI image data were systematically evaluated by a pediatric neuroradiologist for image quality using an ordinal scoring scheme: 1. diagnostic; 2. diagnostic with artifacts; and 3. nondiagnostic. The best score in an individual fetus was used for further statistical analysis. Visibility of venous vasculature was also scored using a dichotomous variable. A subset of SWI data was re‐evaluated by the first and independently by a second pediatric neuroradiologist. Kappa coefficients were computed to assess intra‐rater and inter‐rater reliability.

Results

SWI image data from a total of 22 fetuses were analyzed. Median gestational age and interquartile range of the fetuses imaged were 32 (29.9–34.9) weeks. In 68.2% of the cases (n = 15), there was no artifact; 22.7% (n = 5) had minor artifacts and 9.1% (n = 2) of the data was of nondiagnostic quality. Cerebral venous vasculature was visible in 86.4% (n = 19) of the cases. Substantial agreement (Kappa = 0.73; 95% confidence interval 0.44–1.00)) was observed for intra‐rater reliability and moderate agreement (Kappa = 0.48; 95% confidence interval 0.19–0.77) was observed for inter‐rater reliability.

Conclusion

It is feasible to perform fetal brain venography in humans using SWI. J. Magn. Reson. Imaging 2014;40:949–957. © 2013 Wiley Periodicals, Inc.
The Erk MAP kinase pathway is activated at muscle spindles and is required for induction of the muscle spindle‐specific gene Egr3 by neuregulin1
Authors: Herndon Carter A. , Ankenbruck Nick , Fromm Larry
Published: November 2013

Muscle spindles are sensory receptors composed of specialized muscle fibers, known as intrafusal muscle fibers, along with the endings of sensory neuron axons that innervate these muscle fibers. Formation of muscle spindles requires neuregulin1 (NRG1), which is released by sensory axons, activating ErbB receptors in muscle cells that are contacted. The transcription factor Egr3 is transcriptionally induced by NRG1, which in turn activates various target genes involved in forming intrafusal fibers. We have previously shown that, in cultured muscle cells, NRG1 signaling activates the Egr3 gene through SRF and CREB, which bind to a composite regulatory element, and that NRG1 signaling targets SRF by stimulating nuclear translocation of SRF coactivators myocardin‐related transcription factor (MRTF)‐A and MRTF‐B and targets CREB by phosphorylation. The current studies examined signaling relays that might function in the NRG1 pathway upstream of SRF and CREB. We found that transcriptional induction of Egr3 in response to NRG1 requires the MAP kinase Erk1/2, which acts upstream of CREB to induce its phosphorylation. MRTFs are targeted by the Rho‐actin pathway, yet in the absence of Rho‐actin signaling, even though MRTFs fail to be translocated to the nucleus, NRG1 induces Egr3 transcription. In mouse muscle in vivo, activation of Erk1/2 is enhanced selectively where muscle spindles are located. These results suggest that Erk1/2 acts in intrafusal fibers of muscle spindles to induce transcription of Egr3 and that Egr3 induction occurs independently of MRTFs and involves Erk1/2 acting on other transcriptional regulatory targets that interact with the SRF‐CREB regulatory element. © 2013 Wiley Periodicals, Inc.
Mildronate improves cognition and reduces amyloid‐β pathology in transgenic Alzheimer's disease mice
Authors: Beitnere Ulrika , van Groen Thomas , Kumar Ashish , Jansone Baiba , Klusa Vija , Kadish Inga
Published: November 2013

Mildronate, a carnitine congener drug, previously has been shown to provide neuroprotection in an azidothymidine‐induced mouse model of neurotoxicity and in a Parkinson's disease rat model. The aim of this study was to investigate the effects of mildronate treatment on cognition and pathology in Alzheimer's disease (AD) model mice (APPSweDI). Mildronate was administered i.p. daily at 50 or 100 mg/kg for 28 days. At the end of treatment, the animals were behaviorally and cognitively tested, and brains were assessed for AD‐related pathology, inflammation, synaptic markers, and acetylcholinesterase (AChE). The data show that mildronate treatment significantly improved animal performance in water maze and social recognition tests, lowered amyloid‐β deposition in the hippocampus, increased expression of the microglia marker Iba‐1, and decreased AChE staining, although it did not alter expression of proteins involved in synaptic plasticity (GAP‐43, synaptophysin, and GAD67). Taken together, these findings indicate mildronate's ability to improve cognition and reduce amyloid‐β pathology in a mouse model of AD and its possible therapeutic utility as a disease‐modifying drug in AD patients. © 2013 Wiley Periodicals, Inc.
Trends in extreme rainfall and temperature indices in the western Thailand
Authors: Sharma Devesh , Babel Mukand Singh
Published: November 2013

Trends in extreme daily temperature and rainfall have been analysed from 1961 to 2002 for the western Thailand (Mae Ping and Mae Klong river basins). Daily precipitation, maximum and minimum temperature data for 15 stations were analysed to calculate 21 extreme indices. The magnitude of trends was estimated using the linear regression method while its statistical significance was evaluated using the p‐value at 5% significance level and Kendall‐tau test. The result of the analysis depicts significant increase in the annual number of warm days and warm nights, with corresponding significant decreases in the annual number of cool days and cold nights. The warm spell duration indicator presents statistical rising trends. The trends for temperature indices are more consistent in the region compared to precipitation indices. There is insignificant decrease in annual total precipitation for nearly all stations. The maximum number of consecutive dry days (rain less than 1 mm) is increasing. The number of days with rainfall more than 10 and 20 mm has declined over both basins except at Kanchanaburi station. Analysis also reveals that there is less spatial coherent in other extreme indicators, namely, maximum 1‐day and 5‐days rainfall amount and simple daily intensity index.
Preparation and characterisation of a stable silver colloid for SER(R)S spectroscopy
Authors: White P. , Hjortkjaer J.
Published: November 2013

A method for the reproducible preparation of a silver colloid with strong surface‐enhanced Raman scattering (SERS) properties, good stability with a zeta potential of −55 mV and a shelf life exceeding 1 year is reported. The mean particle size is 20 nm with a narrow size distribution of 10–30 nm. The colloid is produced by the reduction of silver nitrate with hydroxylamine phosphate to give a negatively charged phosphate surface on the silver particles. This is an ultrafast room temperature reaction and with controlled rapid addition and dispersion of reagents, very reproducible batches of colloid can be prepared making it suitable for commercial applications of Surface enhanced resonance Raman scattering(SER(R)S) spectroscopy. The stability of the colloid is attributed to the extremely low solubility product (Ksp) of silver phosphate. Characterisation and stability study data for this colloid have been obtained by ultraviolet–visible spectroscopy, transmission electron microscopy, energy dispersive X‐ray spectroscopy, particle size analysis and SERS analyses using a 514 nm laser on a Raman spectrometer. A SERS method to detect and to identify riboflavin in a vitamin B complex tablet is reported to illustrate a SERS application based upon the use of this silver colloid. Copyright © 2013 John Wiley & Sons, Ltd.
Metachronous colorectal cancer: A competing risks analysis with consideration for a stratified approach to surveillance colonoscopy
Authors: Battersby Nicholas J. , Coupland Alex , Bouliotis George , Mirza Nazzia , Williams J. Graham
Published: November 2013

Background

The incidence of metachronous cancer will become an important clinical consideration as the life expectancy of the population increases and as rates of curative resection improve.

Objective

To assess the pattern of metachronous cancer development following curative resection of colorectal cancer in an unselected patient population offered postoperative colonoscopic surveillance.

Method

Prospective clinical follow‐up after curative colorectal cancer resection and surveillance colonoscopy with or without polypectomy in accordance with the national guidelines. Actuarial analysis and competing risk analysis were performed to account for death and recurrence and to stratify for age, gender, stage, and tumor site.

Results

Five hundred thirty‐eight patients with median follow‐up 4 years 2 month (0–16) years. Fifteen patients (3%) developed metachronous cancer, at a median time interval of 90 months from primary resection. Thirteen metachronous cancer patients (87%, 13/15) underwent one to five surveillance colonoscopies: nine patients were asymptomatic at time of diagnosis of metachronous cancer. Competing risks analysis suggests that the adjusted cumulative incidence in males aged 55 is 4% at 10 years compared with 1% in females aged 85 years old.

Conclusions

A patient aged under 65 at the time of the primary curative resection carries a 2% 5‐year risk of metachronous cancer, implying that 3 year surveillance colonoscopy is justified. Whereas patients aged over 75 carry less than a 2% 10‐year risk, implying that it is seldom warranted to repeat the colonoscopy more frequently than every 5 years. A stratified approach to the frequency of surveillance colonoscopy requires further consideration. J. Surg. Oncol. 2014 109:445–450. © 2013 Wiley Periodicals, Inc.
Prognostic factors for medium‐ and long‐term survival of esophageal cancer patients in the Netherlands
Authors: Bus Pauline , Lemmens Valery E. , van Oijen Martijn G. , Creemers Geert‐Jan , Nieuwenhuijzen Grard A. , van Baal Jantine W. , Siersema Peter D.
Published: November 2013

Background and Objectives

Medium‐ and long‐term survival is low in esophageal cancer (EC) patients, which is thought to be due to tumor characteristics. Our aim was to determine both tumor‐ and non‐tumor‐related characteristics affecting survival in these patients.

Methods

Patients with primary EC between 1990 and 2008 in the southern part of the Netherlands were identified. Multivariable logistic regression was used to identify determinants of survival.

Results

In total, 703 patients with EC were included for the 1‐year, 551 for the 3‐year and 436 for the 5‐year survival analysis. Poor 1‐year survival was independently associated with chemoradiation (compared to surgery), positive lymph nodes (N1‐stage) and 1 or ≥2 comorbidities. Adenocarcinoma (EAC) compared to squamous cell carcinoma was significantly associated with a better 1‐year survival. Poor 3‐ and 5‐year survival was associated with N1‐stage and chemoradiation. Positive prognostic factors for 3‐ and 5‐year survival were neoadjuvant therapy and female gender.

Conclusion

Both tumor‐related (negative lymph nodes and EAC histology) and non‐tumor‐related factors (surgery, neoadjuvant therapy, and female gender) are associated with a better survival of EC. Although it is not clear how histology and gender affect EC survival, knowledge of these factors may be relevant for clinical decision making. J. Surg. Oncol. 2014 109:465–471. © 2013 Wiley Periodicals, Inc.
Thinking About Trauma: The Unique Contributions of Event Centrality and Posttraumatic Cognitions in Predicting PTSD and Posttraumatic Growth
Authors: Barton Sarah , Boals Adriel , Knowles Laura
Published: November 2013

Researchers have been investigating possible pathways to negative (posttraumatic stress disorder [PTSD]) and positive (posttraumatic growth [PTG]) reactions to trauma in recent decades. Two cognitive constructs, event centrality and posttraumatic cognitions, have been implicated to uniquely predict PTSD symptoms in an undergraduate sample. The current pair of studies attempted to (a) replicate this finding in an undergraduate sample, (b) replicate this finding in a treatment‐seeking sample, and (c) explore whether these 2 cognitive constructs uniquely predict PTG. The first study consisted of 500 undergraduate students, whereas the second study consisted of 53 treatment‐seeking clients. Results indicated both posttraumatic cognitions and event centrality uniquely predicted PTSD in the undergraduate (R2 = .46) and treatment‐seeking samples (R2 = .46). These 2 cognitive constructs also predicted PTG in the undergraduate sample (R2 = .37), but only posttraumatic cognitions predicted PTG in the treatment‐seeking sample (R2 = .17). The relationships between PTG varied, depending on whether PTG for high or low event‐centrality events were assessed. The original model was supported within both populations for PTSD symptoms, and its extension to PTG was supported within the treatment‐seeking sample. These results underscore cognitive and narrative factors in the progression of trauma.
Moderating Effects of a Postdisaster Intervention on Risk and Resilience Factors Associated With Posttraumatic Stress Disorder in Chinese Children
Authors: Fu Christine , Leoutsakos Jeannie‐Marie , Underwood Carol
Published: November 2013

This study is an evaluation of a psychosocial intervention involving child and adolescent survivors of the 2008 Sichuan China earthquake. Sociodemographics, earthquake‐related risk exposure, resilience using the Connor‐Davidson Resilience Scale, and posttraumatic stress disorder (PTSD) using the UCLA‐PTSD Index were collected from 1,988 intervention participants and 2,132 controls. Mean resilience scores and the odds of PTSD did not vary between groups. The independent factors for risk and resilience and the dependent variable, PTSD, in the measurement models between control and intervention groups were equivalent. The structural model of risk and 2 resilience factors on PTSD was examined and found to be unequivalent between groups. In contrast to controls, risk exposure (B = −0.32, p < .001) in the intervention group was negatively associated with PTSD. Rational thinking (B = −0.48, p < .001), a resilience factor, was more negatively associated with PTSD in the intervention group. The second resilience factor explored, self‐awareness, was positively associated with PTSD in both groups (B = 0.46 for controls, p < .001, and B = 0.69 for intervention, p < .001). Results highlight the need for more cross‐cultural research in resilience theory to develop culturally appropriate interventions and evaluation measures.
TRASER: Dye cell aspect ratio and parallel vs. sequential pulsing and their relation to energy output
Authors: Gustavsson Morgan , Spanogle Joshua P. , Berganza Leo , Zachary Christopher B.
Published: November 2013

Background and Objective

This paper examines some characteristics of the newly described TRASER (total reflection amplification of spontaneous emission of radiation) device, particularly with regard to dye cell aspect‐ratio and parallel vs. sequential pulsing, and their relation to energy output. We also examine the association of electrical tension (voltage) over the flash lamps and the pulse train composition with the energy output.

Materials and Methods

Using a TRASER with design and specifications previously described, a variety of standard output measurements were made while varying a single parameter, namely voltage over the flashlamps, pulse train formation, dye cell aspect‐ratio, and utilization of parallel and sequential pulsing.

Results

There was a linear association of energy output with the electrical tension over the arc lamps. Longer pulse trains resulted in dramatically increased energy output. An increase in dye cell aspect ratio resulted in proportional increases in energy output. Sequential pulsing provided significantly more energy than parallel pulsing at all but the shortest pulse durations.

Conclusion

These findings are of critical importance to the understanding and optimization of the output characteristics of a TRASER. These can be utilitzed to provide high fluences, very large spot sizes, and variable pulse widths, all important features that can be manipulated to achieve better clinical outcomes in practice. Lasers Surg. Med. 46:140–143, 2014. © 2013 Wiley Periodicals, Inc.
Atomistic Simulation of the Shape‐Memory Effect in Dry and Water Swollen Poly[(rac‐lactide)‐co‐glycolide] and Copolyester Urethanes Thereof
Authors: Ghobadi Ehsan , Heuchel Matthias , Kratz Karl , Lendlein Andreas
Published: November 2013

An atomistic molecular dynamics simulation approach is applied to model the influence of urethane linker units as well as the addition of water molecules on the simulated shape‐memory properties of poly[(rac‐lactide)‐co‐glycolide] (PLGA) and PLGA‐based copolyester urethanes comprising different urethane linkers. The shape‐memory performance of these amorphous packing models is explored in a simulated heating–deformation–cooling–heating procedure. Depending on the type of incorporated urethane linker, the mechanical properties of the dry copolyester urethanes are found to be significantly improved compared with PLGA, which can be attributed to the number of intermolecular hydrogen bonds between the urethane units. Good shape‐memory properties are observed for all the modeled systems. In the dry state, the shape fixation is found to be improved by implementation of urethane units. After swelling of the copolymer models with water, which results in a reduction of their glass transition temperatures, the relaxation kinetics during unloading and shape recovery are found to be substantially accelerated.

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Tunable Dual‐Thermoresponsive Phase Behavior of Zwitterionic Polysulfobetaine Copolymers Containing Poly(N,N‐dimethylaminoethyl methacrylate)‐Grafted Silica Nanoparticles in Aqueous Solution
Authors: Dong Zhixin , Mao Jun , Wang Dapeng , Yang Muquan , Wang Weicai , Bo Shuqin , Ji Xiangling
Published: November 2013

Novel thermoresponsive copolymers of zwitterionic sulfobetaine methacrylate (SBMA)‐ and N,N‐dimethylaminoethyl methacrylate (DMAEMA)‐grafted silica nanoparticles are prepared via surface‐initiated atom transfer radical polymerization. The phase behavior of these nanoparticles is investigated. The hybrid nanoparticles exhibit tunable phase transition temperature between the upper critical solution temperature (UCST) and the lower critical solution temperature (LCST) in aqueous solution. A high PSBMA content in P(SBMA‐co‐DMAEMA) copolymer in the hybrid nanoparticles leads to aggregation at low temperatures because of dominant electrostatic interactions of ionic pairs, whereas a relatively low PSBMA content in the hybrid nanoparticles results in a phase transition at high temperatures as a result of predominant hydrophobic interactions of the PDMAEMA. Interestingly, hybrid nanoparticles with a suitable molar ratio of SBMA/DMAEMA exhibit both UCST and LCST in aqueous solution, where the water‐insoluble microdomains of hybrid nanoparticles are generated by the PSBMA or PDMAEMA region depending on the temperature. The above dual‐thermoresponsive phase transition is also controllable in salt solution. A facile change in the molar content of copolymer grafted on silica nanoparticles will tune the UCST and LCST readily.

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Contribution of High‐shear Processing to the Compatibilization of (PP/EPR)/PE Ternary Blends
Authors: Louizi Molka , Massardier Valérie , Cassagnau Philippe
Published: November 2013

The novel compatibilization of high impact polypropylene/high density polyethylene (PP/EPR)/PE blends by high shear process leads to a typical core–shell structure, with PE core encapsulated by EPR shell within PP matrix, a decrease of the size of (PE/EPR) domains as well as an improvement of the interface being observed when increasing screw rotation speed from 300 to 600 rpm. Possible in situ formation of copolymers can be an explanation for the improved miscibility between phases. Further, the addition of only 3 wt.‐% of ethylene‐octene copolymer (EOC) to the (PP/EPR)/PE blend processed at 600 rpm increases elongation at break and impact strength by respectively 80 and 100% as EPR and EOC could play a synergetic role. This novel process offers new perspectives for lightening and recycling.
Smoothness of the Orlicz norm in Musielak–Orlicz function spaces
Authors: Vigelis Rui F. , Cavalcante Charles C.
Published: November 2013

In this paper, we present a characterization of support functionals and smooth points in , the Musielak–Orlicz space equipped with the Orlicz norm. As a result, criterion for the smoothness of is also obtained. Some expressions involving the norms of functionals in , the topological dual of , are proved for arbitrary Musielak–Orlicz functions.
Extreme self‐adjoint extensions of a semibounded ‐difference operator
Authors: B. Bekker Miron , J. Bohner Martin , Voulov Hristo
Published: November 2013

For a certain q‐difference operator introduced and studied in a series of articles by the same authors, we investigate its extreme self‐adjoint extensions, i.e., the so‐called Friedrichs and Kreĭn extensions. We show that for the interval of parameters under consideration, the Friedrichs extension and the Kreĭn extension are distinct and give values of the parameter in the von Neumann formulas that correspond to those extensions and describe their resolvent operators. A crucial rôle in our investigation plays the fact that both the Friedrichs and the Kreĭn extensions are scale invariant.
Efficient Synthesis of High Purity Homo‐arm and Mikto‐arm Poly(ethylene glycol) Stars Using Epoxide and Azide–Alkyne Coupling Chemistry
Authors: Zhang Boyu , Zhang Hong , Elupula Ravinder , Alb Alina M. , Grayson Scott M.
Published: November 2013

High purity homo‐arm and mikto‐arm poly(ethylene glycol) (PEG) stars are successfully prepared by the combination of epoxide ring‐openings and azide–alkyne click reactions. First, monohydroxy‐PEG was modified via epoxide chemistry to bear one hydroxyl and one azide functionality at the same end. An alkyne‐functionalized PEG chain was then coupled to the azide. Subsequently, the remaining hydroxyl could be reactivated to an azide again and again to enable stepwise addition of alkyne‐functionalized polymer arms. The use of efficient reactions for this iterative route provides star polymers with an exact number of arms, and a tailorable degree of polymerization for each arm. Detailed characterization confirms the high purity of multi‐arm polyethylene glycol products.

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Pathophysiology of tobacco smoke exposure: Recent insights from comparative and redox proteomics
Authors: Colombo Graziano , Clerici Marco , Giustarini Daniela , Portinaro Nicola M. , Aldini Giancarlo , Rossi Ranieri , Milzani Aldo , Dalle‐Donne Isabella
Published: November 2013

First‐hand and second‐hand tobacco smoke are causally linked to a huge number of deaths and are responsible for a broad spectrum of pathologies such as cancer, cardiovascular, respiratory, and eye diseases as well as adverse effects on female reproductive function. Cigarette smoke is a complex mixture of thousands of different chemical species, which exert their negative effects on macromolecules and biochemical pathways, both directly and indirectly. Many compounds can act as oxidants, pro‐inflammatory agents, carcinogens, or a combination of these. The redox behavior of cigarette smoke has many implications for smoke related diseases. Reactive oxygen and nitrogen species (both radicals and non‐radicals), reactive carbonyl compounds, and other species may induce oxidative damage in almost all the biological macromolecules, compromising their structure and/or function. Different quantitative and redox proteomic approaches have been applied in vitro and in vivo to evaluate, respectively, changes in protein expression and specific oxidative protein modifications induced by exposure to cigarette smoke and are overviewed in this review. Many gel‐based and gel‐free proteomic techniques have already been used successfully to obtain clues about smoke effects on different proteins in cell cultures, animal models, and humans. The further implementation with other sensitive screening techniques could be useful to integrate the comprehension of cigarette smoke effects on human health. In particular, the redox proteomic approach may also help identify biomarkers of exposure to tobacco smoke useful for preventing these effects or potentially predictive of the onset and/or progression of smoking‐induced diseases as well as potential targets for therapeutic strategies. © 2013 Wiley Periodicals, Inc. Mass Spec Rev 33: 183–218, 2014.
Cytokines in ovarian folliculogenesis, oocyte maturation and luteinisation
Authors: Field Sarah L , Dasgupta Tathagata , Cummings Michele , Orsi Nicolas M.
Published: November 2013

Cytokines are key regulators of ovarian physiology, particularly in relation to folliculogenesis and ovulation, where they contribute to creating an environment supporting follicle selection and growth. Their manifold functions include regulating cellular proliferation/differentiation, follicular survival/atresia, and oocyte maturation. Several cytokines, such as TGF‐β‐superfamily members, are involved at all stages of folliculogenesis while the production of others is stage‐dependent. This review draws upon evidence from both human and animal models to highlight the species‐specific roles at each milestone of follicular development. Given these pivotal roles and their ease of detection in follicular fluid, cytokines have been considered as attractive biomarkers of oocyte maturational status and of successful assisted reproductive outcome. Despite this, our understanding of cytokines and their interactions remains incomplete, and is still frequently limited to overly simplistic descriptions of their interrelationships. Given our increased appreciation of cytokine activity in complex and highly regulated networks, we put forward the case for using Bayesian modelling approaches to describe their hierarchical relationships in order to predict causal physiological interactions in vivo. Mol. Reprod. Dev. 81: 284–314, 2014. © 2013 Wiley Periodicals, Inc.
Predictors of wait‐time for antibiotic initiation and association of wait‐time with hospital length of stay and ICU admission among children with cancer at the Southern Philippines Medical Center
Authors: Kirby Jeannette , Dolendo Mae , Guimera Don , Castillo Czarina , Johnson Kyle M. , Mzayek Fawaz , Nolan Vikki G. , Relyea George , Caniza Miguela A.
Published: November 2013

Background

Expedited antibiotic administration improves the survival of children with cancer and infection. A 1‐hour antibiotic wait‐time (AWT) post‐hospital arrival is a quality‐of‐care benchmark in healthcare. However, multiple factors preclude achieving this goal in developing countries. Predictors of AWT and its association with hospital length of stay (LOS) and intensive care unit (ICU) admission at the Southern Philippines Medical Center (SPMC) were identified.

Procedures

Health and socioeconomic characteristics of 55 children in 92 admissions who required antibiotics were reviewed; and SPMC care providers about institutional capacity and response to suspected infection were surveyed.

Results

The mean total AWT was 3 days and 15 hours. For admissions of established patients, mean total AWT and mean LOS were approximately half that for new patients. Admissions from high‐income households waited an average 44% less for antibiotics and were discharged 43% sooner than those from medium‐income households. Admissions from residence owner families waited 31% less to receive antibiotics, and total AWT for admissions of patients with no insurance was 32% less than for those with insurance. The likelihood of ICU admission increased 20% with every 1‐day increase in total AWT (95% CI: 1.02 1.42). Only 59% of nurses recognized fever as an emergency.

Conclusions

AWT is complex and multifactorial; it may be reduced by educating parents and care providers about infection and infection control and improving the availability of antibiotics and associated supplies. These interventions will most likely reduce ICU admissions and possibly LOS and increase the survival of pediatric oncology patients at SPMC. Pediatr Blood Cancer 2014;61:680–686. © 2013 Wiley Periodicals, Inc.