bluuebunny/crossref_metadata_2025 huggingface dataset:
Interaction of citrate‐coated silver nanoparticles with earthworm coelomic fluid and related cytotoxicity in Eisenia andrei
Authors: Kwak Jin Il , Lee Woo‐Mi , Kim Shin Woong , An Youn‐Joo
Published: February 2014

Understanding the interaction of nanoparticles with biological fluid is important for predicting the behavior and toxicity of nanoparticles in living systems. The earthworm Eisenia andrei was exposed to citrate‐coated silver nanoparticles (cAgNPs), and the interaction of cAgNPs with earthworm coelomic fluid (ECF), the cytotoxicity of cAgNPs in earthworm coelomocytes was assessed. The neutral red retention assay showed a reduction in lysosomal stability after exposure. The toxicity of silver ions dissolved from cAgNPs in the soil medium was not significant. The aggregation and dissolution of cAgNPs increased in ECF, which contains various electrolytes that alter the properties of nanoparticles, and their subsequent toxicity. Microscopic and dissolution studies demonstrated that the aggregation of cAgNPs rapidly increased, and readily dissolved in ECF. The bioavailability of cAgNPs to earthworms induced lysosomal cytotoxicity. This is the first report to test the interaction and lysosomal cytotoxicity of nanoparticles in earthworm biofluids. Copyright © 2014 John Wiley & Sons, Ltd.
Carbon‐based nanomaterials accelerate arteriolar thrombus formation in the murine microcirculation independently of their shape
Authors: Holzer Martin , Bihari Peter , Praetner Marc , Uhl Bernd , Reichel Christoph , Fent Janos , Vippola Minnamari , Lakatos Susan , Krombach Fritz
Published: February 2014

Although carbon‐based nanomaterials (CBNs) have been shown to exert prothrombotic effects in microvessels, it is poorly understood whether CBNs also have the potential to interfere with the process of leukocyte‐endothelial cell interactions and whether the shape of CBNs plays a role in these processes. Thus, the aim of this study was to compare the acute effects of two differently shaped CBNs, fiber‐shaped single‐walled carbon nanotubes (SWCNT) and spherical ultrafine carbon black (CB), on thrombus formation as well as on leukocyte‐endothelial cell interactions and leukocyte transmigration in the murine microcirculation upon systemic administration in vivo. Systemic administration of both SWCNT and CB accelerated arteriolar thrombus formation at a dose of 1 mg kg–1 body weight, whereas SWCNT exerted a prothrombotic effect also at a lower dose (0.1 mg kg–1 body weight). In vitro, both CBNs induced P‐selectin expression on human platelets and formation of platelet‐granulocyte complexes. In contrast, injection of fiber‐shaped SWCNT or of spherical CB did not induce leukocyte–endothelial cell interactions or leukocyte transmigration. In vitro, both CBNs slightly increased the expression of activation markers on human monocytes and granulocytes. These findings suggest that systemic administration of CBNs accelerates arteriolar thrombus formation independently of the CBNs' shape, but does not induce leukocyte–endothelial cell interactions or leukocyte transmigration. Copyright © 2014 John Wiley & Sons, Ltd.
LUMPAC lanthanide luminescence software: Efficient and user friendly
Authors: Dutra José Diogo L. , Bispo Thiago D. , Freire Ricardo O.
Published: February 2014

In this study, we will be presenting LUMPAC (LUMinescence PACkage), which was developed with the objective of making possible the theoretical study of lanthanide‐based luminescent systems. This is the first software that allows the study of luminescent properties of lanthanide‐based systems. Besides being a computationally efficient software, LUMPAC is user friendly and can be used by researchers who have no previous experience in theoretical chemistry. With this new tool, we hope to enable research groups to use theoretical tools on projects involving systems that contain lanthanide ions. © 2014 Wiley Periodicals, Inc.
The effect of the intermolecular potential formulation on the state‐selected energy exchange rate coefficients in N2–N2 collisions
Authors: Kurnosov Alexander , Cacciatore Mario , Laganà Antonio , Pirani Fernando , Bartolomei Massimiliano , Garcia Ernesto
Published: February 2014

The rate coefficients for N2–N2 collision‐induced vibrational energy exchange (important for the enhancement of several modern innovative technologies) have been computed over a wide range of temperature. Potential energy surfaces based on different formulations of the intramolecular and intermolecular components of the interaction have been used to compute quasiclassically and semiclassically some vibrational to vibrational energy transfer rate coefficients. Related outcomes have been rationalized in terms of state‐to‐state probabilities and cross sections for quasi‐resonant transitions and deexcitations from the first excited vibrational level (for which experimental information are available). On this ground, it has been possible to spot critical differences on the vibrational energy exchange mechanisms supported by the different surfaces (mainly by their intermolecular components) in the low collision energy regime, though still effective for temperatures as high as 10,000 K. It was found, in particular, that the most recently proposed intermolecular potential becomes the most effective in promoting vibrational energy exchange near threshold temperatures and has a behavior opposite to the previously proposed one when varying the coupling of vibration with the other degrees of freedom. © 2014 Wiley Periodicals, Inc.
Maxima of : A connection between quantum mechanics and Lewis structures
Authors: Lüchow Arne
Published: February 2014

The maxima of squared electronic wave functionsare analyzed for a number of small molecules. They are in principle observables and show considerable chemical insight from first principles. The maxima contain substantial information about the relative electron positions in a molecule, such as the pairing of opposite spin electrons and the Pauli repulsion which are lost in the electron density. Single bond and double bond as well as polar bond pairs and lone pairs are obtained from the maximum analysis. In many cases, we find a correspondence to the electron arrangements in molecules as assumed by Lewis in 1916. © 2014 Wiley Periodicals, Inc.
Oligoepicatechins from the Leaves of Machilus konishii
Authors: Lin Yi‐Shan , Tsai Sheng‐Fa , Lee Shoei‐Sheng
Published: February 2014

Epicatechin (3) and five oligomers (2, 4, 5, 10, 11) together with five other type compounds were isolated and characterized from n‐BuOH and EtOAc soluble fractions of the ethanol extract of the leaves of Machilus konishii Hayata. Their structures were elucidated by means of MS and NMR spectroscopic analyses. Dehydrodiepicatechin A (11) is the first occurrence as a natural product although it has been prepared from epicatechin. The stereochemistry of 11 is elucidated for the first time on the basis of 1D NOESY and chemical model analyses. Tiliroside (7) and kaempferol 3‐O‐α‐L‐(2″,4″‐di‐E‐p‐coumaroyl)‐rhamnopyranoside (8) showed moderate inhibitory activity against α‐glucosidase.
Synthesis and Micellar Behaviors of an Anionic Polymerizable Surfactant
Authors: Ma Lihua , Guo Yongjun , Feng Rusheng , Xiang Panpan , Li Chunhui
Published: February 2014

A novel anionic polymerizable surfactant sodium (5‐acryloyl‐2‐(dodecyloxy)phenyl) methane sulfonate has been synthesized from phenol, acrylic acid and bromododecane by esterification, Frise rearrangement, sulfomethylation reaction and Williamson etherification. The parameters of the micellar behaviors are as follows: The CMC was 150 ppm at 40 °C; The surface absorption amounts Γm was 3.208 × 10−6 mol m−2; The molecular areas Am was 0.550 × 10−18m2 at the interface of air‐water respectively; The aggregation number (Nagg) at C = CMC of this surfactant was 12.
In vitro Toxicological Study of Metal Oxides Nanoparticles on Oxidation of Succinate in Krebs Cycle and Their Resultant Effect in Metabolic Pathways
Authors: Tanveer Samreen , Farrukh Muhammad Akhyar , Ali Shaista , Khaleeq‐ur‐Rahman Muhammad , Imtiaz Ayesha
Published: February 2014

In vitro study to evaluate toxic effects of metal oxides nanoparticles on energy producing cycle was conducted. In this study oxidation of sodium succinate in aqueous solution was investigated by using potassium ferricyanide as an oxidizing agent. Kinetic measurements were carried out on kinetic mode of spectrophotometer at λmax 420 nm. Effect of different metal oxides (MgO and CaO) nanoparticles was observed on the oxidation of succinate at 25 ± 0.5 °C. These metal oxides nanoparticles were prepared by hydrothermal method and their characterization were done by using FTIR, TGA, SEM‐EDX, TEM and XRD. Kinetic results indicated that these nanoparticles inhibit the conversion of succinate into fumerate. The inhibition is directly dependent on particle size of the nanoparticles and it was observed that particle size is inversely related to the oxidation rate of succinate. It was concluded at the end that elevated concentrations of metal oxides nanoparticles can severely affect the Krebs cycle by inhibiting succinate oxidation and lead to various metabolic disorders.
Proteasome Modulator 9 Gene SNPs, Responsible for Anti‐Depressant Response, Are in Linkage With Generalized Anxiety Disorder
Authors: Gragnoli Claudia
Published: February 2014

Proteasome modulator 9 (PSMD9) gene single nucleotide polymorphism (SNP) rs1043307/rs2514259 (E197G) is associated with significant clinical response to the anti‐depressant desipramine. PSMD9 SNP rs74421874 [intervening sequence (IVS) 3 + nt460 G>A], rs3825172 (IVS3 + nt437 C>T) and rs1043307/rs2514259 (E197G A>G) are all linked to type 2 diabetes (T2D), maturity‐onset‐diabetes‐of the young 3 (MODY3), obesity and waist circumference, hypertension, hypercholesterolemia, T2D‐macrovascular and T2D‐microvascular disease, T2D‐neuropathy, T2D‐carpal tunnel syndrome, T2D‐nephropathy, T2D‐retinopathy, non‐diabetic retinopathy and depression. PSMD9 rs149556654 rare SNP (N166S A>G) and the variant S143G A>G also contribute to T2D. PSMD9 is located in the chromosome 12q24 locus, which per se is in linkage with depression, bipolar disorder and anxiety. In the present study, we wanted to determine whether PSMD9 is linked to general anxiety disorder in Italian T2D families. Two‐hundred Italian T2D families were phenotyped for generalized anxiety disorder, using the diagnostic criteria of DSM‐IV. When the diagnosis was unavailable or unclear, the trait was reported as unknown. The 200 Italians families were tested for the PSMD9 T2D risk SNPs rs74421874 (IVS3 + nt460 G>A), rs3825172 (IVS3 +nt437 T>C) and for the T2D risk and anti‐depressant response SNP rs1043307/rs2514259 (E197G A>G) for evidence of linkage with generalized anxiety disorder. Non‐parametric linkage analysis was executed via Merlin software. One‐thousand simulation tests were performed to exclude results due to random chance. In our study, the PSMD9 gene SNPs rs74421874, rs3825172, and rs1043307/rs2514259 result in linkage to generalized anxiety disorder. This is the first report describing PSMD9 gene SNPs in linkage to generalized anxiety disorder in T2D families. J. Cell. Physiol. 229: 1157–1159, 2014. © 2014 Wiley Periodicals, Inc.
Adiponectin as Novel Regulator of Cell Proliferation in Human Glioblastoma
Authors: Porcile Carola , Di Zazzo Erika , Monaco Maria Ludovica , D'Angelo Giorgia , Passarella Daniela , Russo Claudio , Di Costanzo Alfonso , Pattarozzi Alessandra , Gatti Monica , Bajetto Adriana , Zona Gianluigi , Barbieri Federica , Oriani Giovannangelo , Moncharmont Bruno , Florio Tullio , Daniele Aurora
Published: February 2014

Adiponectin (Acrp30) is an adipocyte‐secreted hormone with pleiotropic metabolic effects, whose reduced levels were related to development and progression of several malignancies. We looked at the presence of Acrp30 receptors in human glioblastomas (GBM), hypothesizing a role for Acrp30 also in this untreatable cancer. Here we demonstrate that human GBM express Acrp30 receptors (AdipoR1 and AdipoR2), which are often co‐expressed in GBM samples (70% of the analyzed tumors). To investigate the effects of Acrp30 on GBM growth, we used human GBM cell lines U87‐MG and U251, expressing both AdipoR1 and AdipoR2 receptors. In these cells, Acrp30 treatment inhibits DNA synthesis and cell proliferation rate, inducing arrest in G1 phase of the cell cycle. These effects were correlated to a sustained activation of ERK1/2 and Akt kinases, upon Acrp30 treatment. Our results suggest that Acrp30 may represent a novel endogenous negative regulator of GBM cell proliferation, to be evaluated for the possible development of novel pharmacological approaches. J. Cell. Physiol. 229: 1444–1454, 2014. © 2014 Wiley Periodicals, Inc.
Ontogenetic change of the weight support pattern in growing dogs
Authors: Helmsmüller Daniela , Anders Alexandra , Nolte Ingo , Schilling Nadja
Published: February 2014

Weight support patterns vary widely among mammals. Differences in how much of the body weight is supported by the fore‐ versus the hind‐limbs are well documented among and within species. Intraindividual variation due to ontogenetic processes has been studied in several hindlimb‐dominated species and consistently showed a caudal shift in the limbs' support roles. We hypothesized that forelimb‐dominated species exhibit a cranial shift in their support pattern and tested this hypothesis by examining the vertical ground reaction forces in growing dogs. Six male Beagle siblings were studied from 9 to 51 postnatal weeks (PW) of age while they trotted on an instrumented treadmill. Ontogenetic shifting in fore‐to‐hind support was evaluated using vertical force ratios (i.e., peak and impulse) as well as the stance time ratio of the fore‐ and the hind‐limbs. Because morphological and kinematic characteristics influence weight support patterns, changes in body shape (i.e., trunk shape), and average limb position were determined. As in adult dogs, the forelimbs carried a greater proportion of the body weight than the hindlimbs at all ages. When the dogs were younger, peak vertical force occurred earlier during stance in the hindlimbs but not the forelimbs. Both the increasing ratio of the vertical force and the increasing ratio of the stance times indicate an increasing weight support by the forelimbs (i.e., 59% at PW9 vs. 63% at PW51). The observed ontogenetic changes in trunk shape and average limb angle were consistent with this cranial shift in weight support.J. Exp. Zool. 321A:254–264, 2014. © 2014 Wiley Periodicals, Inc.
Observation and inpatient status: Clinical impact of the 2‐midnight rule
Authors: Sheehy Ann M. , Caponi Bartho , Gangireddy Sreedevi , Hamedani Azita G. , Pothof Jeffrey J. , Siegal Eric , Graf Ben K.
Published: February 2014

BACKGROUND

In response to growing concern over frequency and duration of observation encounters, the Centers for Medicare and Medicaid Services enacted a rules change on October 1, 2013, classifying most hospital encounters of <2 midnights as observation, and those ≥2 midnights as inpatient. However, limited data exist to predict the impact of the new rule.

OBJECTIVE

To answer the following: (1) Will the rule reduce observation encounter frequency? (2) Are short‐stay (<2 midnights) inpatient encounters often misclassified observation encounters? (3) Do 2 midnights separate distinct clinical populations, making this rule logical? (4) Do nonclinical factors such as time of day of admission impact classification under the rule?

DESIGN, SETTING AND PATIENTS

Retrospective descriptive study of all observation and inpatient encounters initiated between January 1, 2012 and February 28, 2013 at a Midwestern academic medical center.

MEASUREMENTS

Demographics, insurance type, and characteristics of hospitalization were abstracted for each encounter.

RESULTS

Of 36,193 encounters, 4,769 (13.2%) were observation. Applying the new rules predicted a net loss of 14.9% inpatient stays; for Medicare only, a loss of 7.4%. Less than 2‐midnight inpatient and observation stays were different, sharing only 1 of 5 top International Classification of Diseases, 9th Revision (ICD‐9) codes, but for encounters classified as observation, 4 of 5 top ICD‐9 codes were the same across the length of stay. Observation encounters starting before 8:00 am less commonly spanned 2 midnights (13.6%) than later encounters (31.2%).

CONCLUSIONS

The 2‐midnight rule adds new challenges to observation and inpatient policy. These findings suggest a need for rules modification. Journal of Hospital Medicine 2014;9:203–209. © 2014 Society of Hospital Medicine
Risk factors for potentially avoidable readmissions due to end‐of‐life care issues
Authors: Donzé Jacques , Lipsitz Stuart , Schnipper Jeffrey L.
Published: February 2014

BACKGROUND

Repeated hospitalizations are frequent toward the end of life, where each admission should be an opportunity to initiate advance‐care planning to high‐risk patients.

OBJECTIVE

To identify the risk factors for having a 30‐day potentially avoidable readmission due to end‐of‐life care issues among all medical patients.

DESIGN

Nested case‐control study.

SETTING/PATIENTS

All 10,275 consecutive discharges from any medical service of an academic tertiary medical center in Boston, Massachusetts between July 1, 2009 and June 30, 2010.

MEASUREMENTS

A random sample of all the potentially avoidable 30‐day readmissions was independently reviewed by 9 trained physicians to identify the ones due to end‐of‐life issues.

RESULTS

Among 534, 30‐day potentially avoidable readmission cases reviewed, 80 (15%) were due to an end‐of‐life care issue. In multivariable analysis, the following risk factors were significantly associated with a 30‐day potentially avoidable readmission due to end‐of‐life care issues: number of admissions in the previous 12 months (odds ratio [OR]: 1.10 per admission, 95% confidence interval [CI]: 1.02‐1.20), neoplasm (OR: 5.60, 95% CI: 2.85‐10.98), opiate medications at discharge (OR: 2.29, 95% CI: 1.29‐4.07), Elixhauser comorbidity index (OR: 1.16 per 5‐point increase, 95% CI: 1.10‐1.22). The discrimination of the model (C statistic) was 0.85.

CONCLUSIONS

In a medical population, we identified 4 main risk factors that were significantly associated with 30‐day potentially avoidable readmission due to end‐of‐life care issues, producing a model with very good to excellent discrimination. Patients with these risk factors might benefit from palliative care consultation prior to discharge in order to improve end‐of‐life care and possibly reduce unnecessary rehospitalizations. Journal of Hospital Medicine 2014;9:310–314. © 2014 Society of Hospital Medicine
A 99mTc(CO)3‐labeled benzylguanidine with persistent heart uptake
Authors: Oliveira Bruno L. , Morais Maurício , Gano Lurdes , Santos Isabel , Correia João D. G.
Published: February 2014

We describe the synthesis and biological evaluation of the cationic 99mTc–tricarbonyl complex fac‐[99mTc(CO)3(κ3‐L1)]+ (Tc1) anchored by a pyrazole‐diamine‐methylbenzylguanidine‐based ligand (L1), as potentially useful for myocardial imaging. The rhenium complex fac‐[Re(CO)3(κ3‐L1)]+ (Re1) was prepared and characterized as a ‘cold’ surrogate of the radioactive complex. Cell uptake studies in a neuroblastoma cell line suggest that Tc1 uptake mechanism is related to the norepinephrine transporter (NET). Tissue distribution studies in CD1 mice showed that Tc1 presents high initial heart uptake and a slow washout from the heart (7.8 ± 1.3% injected dose per gram (ID/g), 30‐min post‐injection (p.i.); 6.3 ± 1.3% ID/g, 60‐min p.i.), with heart to blood ratios of 11.8 and 9.0 at 30‐ and 60‐min p.i., respectively. The uptake mechanism of Tc1 appears to be similar to that of metaiodobenzylguanidine (MIBG), as it can be reduced by coinjection with nonradioactive MIBG. The biodistribution profile of Tc2, where the benzylguanidine pharmacophore is absent, corroborates the fact that Tc1 does not accumulate in the heart by a simple diffusion mechanism but rather by a NET‐mediated mechanism. The results confirm those obtained in the cell assays. Despite the persistent heart uptake found for Tc1, the high hepatic and renal uptake remains to be improved.
Molecular characterization of hepatitis B virus (HBV) strains circulating in the northern coast of the Persian Gulf and its comparison with worldwide distribution of HBV subgenotype D1
Authors: Pourkarim Mahmoud Reza , Vergote Valentijn , Amini‐Bavil‐Olyaee Samad , Sharifi Zohre , Sijmons Steven , Lemey Philippe , Maes Piet , Alavian Seyed Moayed , Van Ranst Marc
Published: February 2014

Iran is a large country that covers the northern coast of the Persian Gulf. Iranian residents of this coastal region interact closely with people from neighboring countries because of historical and cultural relationships, as well as economic activities. In addition, the inhabitants of this border region have experienced several wars, which have affected public health infrastructures. This study characterized for the first time, the evolution of the full‐length genome of HBV strains in asymptomatic carrier patients living in this particular region. In addition, this study was compared and complemented by a comprehensive evolutionary analysis of the worldwide geographical distribution of HBV subgenotype D1. Evolutionary analysis demonstrates that patients living in the northern coast of the Persian Gulf are mainly infected with HBV subgenotype D1, subtype ayw2. Specific mutations related to advanced liver disease were found more frequently in these strains compared to other strains isolated from asymptomatic carriers from other regions of Iran. This global comprehensive analysis showed that HBV subgenotype D1 strains have a worldwide distribution and that human mobility and immigration had a large impact on dispersal of HBV subgenotype D1, subtype ayw2 in Middle Eastern countries such as Iran, Syria, and Turkey. In addition to association of subtype ayw2 with subgenotype D1, it was demonstrated that other HBV subtypes like adw2, ayw1, and ayw3 are associated with HBV subgenotype D1 in different regions of the world. This study also revealed a remarkable distribution of subgenotype D1, subtype ayw4 although this particular subtype is associated with subgenotype D4 of HBV in European countries. J. Med. Virol. 86:745–757, 2014. © 2014 Wiley Periodicals, Inc.
Give them what they want or give them what they need? Ideology in the study of leadership
Authors: Mumford Michael D. , Fried Yitzhak
Published: February 2014

In recent years, a number of new, values‐based, or ideological models focusing on leader behavior have been proposed. These models include authentic, servant, character‐based, ethical, spiritual, and aesthetic leadership. In the present effort, we argue that these models, despite some differences in key dimensions, are tied together by a focus on moral behavior. The available evidence indicates that these models have only modest predictive power with respect to organizational performance criteria. More centrally, we argue that tests of these models are characterized by significant methodological problems with respect to both measurement and control. Moreover, these models suffer from some serious substantive concerns, including the explicit confounding of leadership and morality, discounting of system impacts, inappropriate assumptions about follower needs, and inappropriate scientific inferences. These models also fail to provide viable new approaches for leader development. We conclude that caution must be exercised when these models are employed as a basis for understanding leadership. Copyright © 2014 John Wiley & Sons, Ltd.
Isolation and characterization of lytic vibriophage against Vibrio cholerae O1 from environmental water samples in Kelantan, Malaysia
Authors: Al‐Fendi Ali , Shueb Rafidah Hanim , Ravichandran Manickam , Yean Chan Yean
Published: February 2014

Water samples from a variety of sources in Kelantan, Malaysia (lakes, ponds, rivers, ditches, fish farms, and sewage) were screened for the presence of bacteriophages infecting Vibrio cholerae. Ten strains of V. cholerae that appeared to be free of inducible prophages were used as the host strains. Eleven bacteriophage isolates were obtained by plaque assay, three of which were lytic and further characterized. The morphologies of the three lytic phages were similar with each having an icosahedral head (ca. 50–60 nm in diameter), a neck, and a sheathed tail (ca. 90–100 nm in length) characteristic of the family Myoviridae. The genomes of the lytic phages were indistinguishable in length (ca. 33.5 kb), nuclease sensitivity (digestible with DNase I, but not RNase A or S1 nuclease), and restriction enzyme sensitivity (identical banding patterns with HindIII, no digestion with seven other enzymes). Testing for infection against 46 strains of V. cholerae and 16 other species of enteric bacteria revealed that all three isolates had a narrow host range and were only capable of infecting V. cholerae O1 El Tor Inaba. The similar morphologies, indistinguishable genome characteristics, and identical host ranges of these lytic isolates suggests that they represent one phage, or several very closely related phages, present in different water sources. These isolates are good candidates for further bio‐phage‐control studies.
The role of changing multiscale temperature variability in extreme temperature events on the eastern and central Tibetan Plateau during 1960–2008
Authors: Song Ci , Pei Tao , Zhou Chenghu
Published: February 2014

Variability is a very important inherent characteristic of climate and it varies on all timescales. It is also considered an important factor regarding changes of extreme events. On the basis of daily temperature records at 63 stations in the eastern and central Tibetan Plateau during 1960–2008, we examine changes of temperature mean, variability and extremes for the region, and study correlations between multiscale temperature variability and various extreme temperature events. Results show that considering the entire study region, a significantly decreasing trend is observed for intra‐annual temperature variability (StdD), whereas a significantly increasing trend is observed for interannual temperature variability (IVT). Further relationships between multiscale temperature variability and temperature extremes over the past 49 years show that IVT is positively correlated with cold/warm nights (TN10/TN90) and warm days (TX90), whereas StdD is positively correlated with cold extremes (TN10/TX10) and negatively correlated with warm extremes (TN90/TX90). Nevertheless, annual mean temperature also plays an important role in the relationships between temperature variability and temperature extremes, for correlations between IVT and cold temperature extremes in two warming periods are quite different. Stations with different temperature trends for mean, variability and extremes in the two warming periods are categorized in the study region, and these temperature characteristics in each category are also affected by local effects, such as elevation, topography and urbanization. However, in strong warming periods, the change of mean temperature still has a dominant effect on extreme temperature events.
The effect of an additional phosphite stabilizer on the properties of radiation cross‐linked vitamin E blends of UHMWPE
Authors: Oral Ebru , Neils Andrew , Yabannavar Pooja , Muratoglu Orhun K.
Published: February 2014

Antioxidant stabilization of radiation cross‐linked ultrahigh molecular weight polyethylene (UHMWPE) has been introduced to improve the oxidative stability of total joint implant bearing surfaces. Blending of an antioxidant with UHMWPE resin powder followed by consolidation and radiation cross‐linking has been cleared by the FDA for use in both total hips and total knees for designs incorporating two antioxidants, namely vitamin E and Covernox™ (a medical grade version of Irganox™ 1010). The antioxidants in the polymer are expected to protect the polymer during consolidation, during radiation cross‐linking, on the shelf before implantation, and in vivo after implantation. To maximize the protection of the polymer afforded by the antioxidant in vivo, a novel approach may be the use of multiple antioxidants, especially to protect the primary antioxidant for a longer period of time. We hypothesized that the addition of a phosphite stabilizer (Irgafos 168™) commonly used in conjunction with hindered phenolic antioxidants in polymer processing could improve the oxidative stability of radiation cross‐linked blends of vitamin E. To test our hypothesis, we prepared UHMWPE blends with 0.05 wt% Irgafos and 0.05 wt% vitamin E and compared its cross‐link density, wear resistance, tensile properties, and impact strength to control blends containing only vitamin E. Our hypothesis was not supported; the cross‐link density of UHMWPE was significantly decreased by the additive without additional benefit to oxidative stability. To our knowledge, this was the first attempt at using multiple stabilizers in medical grade UHMWPE. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:757–761, 2014.
The impact of multiple endpoint dependency on Q and I2 in meta‐analysis
Authors: Thompson Christopher Glen , Becker Betsy Jane
Published: February 2014

A common assumption in meta‐analysis is that effect sizes are independent. When correlated effect sizes are analyzed using traditional univariate techniques, this assumption is violated. This research assesses the impact of dependence arising from treatment‐control studies with multiple endpoints on homogeneity measures Q and I2 in scenarios using the unbiased standardized‐mean‐difference effect size. Univariate and multivariate meta‐analysis methods are examined. Conditions included different overall outcome effects, study sample sizes, numbers of studies, between‐outcomes correlations, dependency structures, and ways of computing the correlation. The univariate approach used typical fixed‐effects analyses whereas the multivariate approach used generalized least‐squares (GLS) estimates of a fixed‐effects model, weighted by the inverse variance–covariance matrix. Increased dependence among effect sizes led to increased Type I error rates from univariate models. When effect sizes were strongly dependent, error rates were drastically higher than nominal levels regardless of study sample size and number of studies. In contrast, using GLS estimation to account for multiple‐endpoint dependency maintained error rates within nominal levels. Conversely, mean I2 values were not greatly affected by increased amounts of dependency. Last, we point out that the between‐outcomes correlation should be estimated as a pooled within‐groups correlation rather than using a full‐sample estimator that does not consider treatment/control group membership. Copyright © 2014 John Wiley & Sons, Ltd.
Learning by doing—teaching systematic review methods in 8 weeks
Authors: Li Tianjing , Saldanha Ian J. , Vedula S. Swaroop , Yu Tsung , Rosman Lori , Twose Claire , N. Goodman Steven , Dickersin Kay
Published: February 2014

Objective

The objective of this paper is to describe the course “Systematic Reviews and Meta‐analysis” at the Johns Hopkins Bloomberg School of Public Health.

Methods

A distinct feature of our course is a group project in which students, assigned to multi‐disciplinary groups, conduct a systematic review. In‐class sessions comprise didactic lectures, hands‐on exercises, demonstrations, discussion, and group work. Students also work outside of class to complete the systematic review. Students evaluated the course at the end of the term. We also surveyed students from 2004 to 2012 to learn more about the long‐term impact of the course.

Results

The course has been offered to more than 800 students since 1995. In our view, aspects that worked well include the hands‐on approach, students working in a multidisciplinary group, intensive interaction with the teaching team, moving to an online approach, and continuous updates of the course content. A persistent issue is the constraint of time. 193 of 211 (91%) survey participants reported that the course is currently useful or as having an impact on their work.

Conclusions

Our experiences have led us to remain committed to a hands‐on approach. Our course serves as a bridge between classroom learning and real‐world practice, and provides an example of teaching systematic review. Copyright © 2014 John Wiley & Sons, Ltd.
Sentinel lymph node biopsy during prophylactic mastectomy: Is there a role?
Authors: Bunting Pamela W. , Cyr Amy E. , Gao Feng , Margenthaler Julie A.
Published: February 2014

Purpose

We investigated rates of occult malignancy in the breast and sentinel lymph nodes (SLNs) in patients undergoing prophylactic mastectomy (PM) and whether routine sentinel lymph node biopsy (SLNB) is justified.

Methods

A retrospective review of our database identified patients undergoing PMs with SLNB. Descriptive statistics were utilized for data summary. A P value of <0.05 was considered significant.

Results

There were 384 patients during the study period who underwent 467 PMs. Of the 467 PMs, 15 (3.2%) cancers were found on final pathology. All 6 of the invasive cancers identified were T1. A total of 682 SLNs were taken for an average of 1.46 SLNs per PM. There were 5 positive SLNs (1.1%). All were in patients undergoing contralateral PM for either history of breast cancer or new diagnosis of breast cancer. Only one patient with a positive SLN was found to have an occult breast malignancy in the PM specimen.

Conclusion

In 467 PMs performed, 15 (3.2%) occult malignancies were found in the breast and 5 (1.1%) positive SLNs were found. Based on these results, the routine use of SLNB at the time of PM is unnecessary and does not warrant the morbidity associated with this procedure. J. Surg. Oncol. 2014 109:747–750. © 2014 Wiley Periodicals, Inc.
Stimuli‐Responsive Capsules Prepared from Regenerated Silk Fibroin Microspheres
Authors: Cheng Cheng , Teasdale Ian , Brüggemann Oliver
Published: February 2014

Microcapsules are synthesized via the self‐assembly of silk‐fibroin microspheres with polycaprolactone in a colliodosome preparation procedure. The microsphere building blocks with controlled diameter are prepared from the naturally occurring biopolymer, silk fibroin, and then act as stabilizers for oil‐in‐water (O/W) emulsion and organized themselves on the surface of chloroform droplets to form the capsules. The concentration of the protein‐based microspheres and the binding polycacrolactone is used to tailor the size, as well as the permeability of the resultant capsules. Furthermore, microencapsulation of fluorescently labeled macromolecules (20–2000 KDa) is demonstrated. The permeability of the capsules is observed to be stimuli responsive, making it possible to incorporate a pH‐triggered payload release from the capsules. The relatively simple preparation of capsules with controlled dimensions and tunable permeability, alongside the biocompatibility and biodegradability of both polymer components makes these promising materials for potential use in smart drug‐delivery systems.
Corrosion behavior of nickel‐containing weathering steel in simulated marine atmospheric environment
Authors: Cheng X. Q. , Tian Y. W. , Li X. G. , Zhou C.
Published: February 2014

The influence of Ni on the corrosion behavior of Ni‐containing weathering steel (Q415NH) was investigated under alternate dry/wet conditions. The results suggested that the addition of Ni shifted the corrosion potential of the steel to the positive direction and lowered the corrosion current density. Furthermore, the addition of Ni was in favor of the formation of a compact and homogeneous inner rust layer (composed of most α‐FeOOH and little β‐FeOOH), leading to enhanced corrosion resistance of the steel in the simulated marine atmosphere.
Investigation on anticorrosion performance of polyaniline‐mesoporous MCM‐41 composites in new water‐based epoxy coating
Authors: Wang N. , Wu Y. H. , Cheng K. Q. , Zhang J.
Published: February 2014

Mesoporous MCM‐41(M(with template)) whose pore channels were filled with cationic surfactant n‐hexadecyltrimethyl‐ammonium bromide (CTAB) and a (hydrophobic) poly(propylene glycol) nucleus terminated by two primary hydroxyl groups (Pluronic F‐127, molecular weight = 11500) inside the pore channels and on the outer surface of the particle, MCM‐41 (M(without template)) whose mixture template inside the pore channels and on the outer surface of the particle were calcinated, were used as new fillers for waterborne epoxy. The corrosion studies were carried out on steel plates coated with formulations containing polyaniline prepared with M(with template) and M(without template). Correspondingly, corrosion performance of the coatings was studied by electrochemical impedance spectroscopy (EIS) in 3.5% NaCl aqueous solution and salt spray test. Coatings prepared from polyaniline (PANI)/M(without template) particles synthesized by in situ polymerization were found to exhibit excellent corrosion resistance much superior to PANI/M(with template) in aggressive environments due to the different interfacial structures between the fillers and the matrix.
Corrosion behavior of electron beam welded duplex stainless steels
Authors: Schmigalla S. , Krasnorutskyi S. , Zinke M. , Heyn A.
Published: February 2014

The corrosion behavior of duplex stainless steels is strongly affected by the austenite–ferrite ratio. With regard to corrosion resistance as well as mechanical properties a balanced ratio between these two microstructural components is desired. Weld seams manufactured by electron beam welding (EBW) generally exhibit very high amounts of ferrite due to a strong loss of nitrogen during the welding process and a very high cooling rate, which can affect the corrosion behavior adversely. Significant improvements can be reached by varying the electron beam guidance and applying multi‐beam technology. This paper considers the pitting corrosion as well as selective corrosion behavior of the welds as a function of the chosen process parameters during EBW. Comparisons with the corrosion performance of manual metal arc and tungsten inert gas welds are also made.
Effect of heat treatment on the microstructure and corrosion behaviour of Mg–Zn alloys
Authors: Bakhsheshi‐Rad H. R. , Hamzah E. , Medraj M. , Idris M. H. , Lotfabadi A. F. , Daroonparvar M. , Yajid M. A. M.
Published: February 2014

Microstructure and corrosion behaviour in simulated body fluid of as‐cast and heat treated Mg–xZn (x = 3 and 6) alloys for different heat treatment times were studied. The results revealed that as‐cast Mg–3Zn alloys consist of Mg12Zn13 phase and α‐Mg matrix, while Mg–6Zn is composed of Mg51Zn20, Mg12Zn13 compounds and α‐Mg matrix. After heat treatment of Mg–6Zn alloy at 340 °C, the Mg51Zn20 phase decomposed to the matrix and Mg12Zn13 while, the microstructure of Mg–3Zn remained unchanged. The results also indicated that heat treatment at 340 °C has little influence on the corrosion behaviour of Mg–3Zn. In contrast, heat treatment improved the corrosion resistance of the Mg–6Zn alloy as the decomposition of the Mg51Zn20 phase decreased micro‐galvanic corrosion. The corrosion resistance of both as‐cast Mg–3Zn and Mg–6Zn alloys marginally improved with increasing heat treatment times.
Involvement of RECK in gambogic acid induced anti‐invasive effect in A549 human lung carcinoma cells
Authors: Qi Qi , Lu Na , Li Chenglin , Zhao Jie , Liu Wei , You Qidong , Guo Qinglong
Published: February 2014

Gambogic acid (GA), a xanthone derived from the resin of theGarcinia hanburyi, has been demonstrated possessing anti‐metastatic activity in vitro and in vivo. Reversion‐inducing cysteine‐rich protein with Kazal motifs (RECK), a membrane‐anchored glycoprotein negatively regulating matrix metalloproteinases (MMPs), plays an important role in tumor invasion and metastasis. The present study investigates the regulatory effect of GA on RECK expression and the role of RECK in GA‐induced anti‐invasion in A549 human lung cancer cells. Our results showed that GA dose‐dependently inhibited cell invasion and suppressed A549 experimental lung metastasis in vivo, which was attributed to RECK up‐regulation at both protein and mRNA levels. With small interference RNA (siRNA) blocking RECK expression, we found inhibition of RECK decreased the GA‐induced inhibition of MMP‐2/9, which was in consistent with the attenuated anti‐invasive effect of GA. Further study indicated that GA effectively suppressed Histone deacetylase (HDAC) 1/specificity protein (Sp) 1 binding and Sp1 phosphorylation associating with Extracellular signal‐regulated kinases (ERK) signaling blocking, leading to RECK up‐regulation. Taken together, these data demonstrate that RECK contributes to GA's anti‐invasive activity and provide new evidence for GA being served as a therapeutic candidate for cancer metastasis. © 2014 Wiley Periodicals, Inc.
Essential tremor is not associated with cerebellar Purkinje cell loss
Authors: Symanski Claire , Shill Holly A. , Dugger Brittany , Hentz Joseph G. , Adler Charles H. , Jacobson Sandra A. , Driver‐Dunckley Erika , Beach Thomas G.
Published: February 2014

There has been controversy as to whether there is an underlying neurodegenerative process of the cerebellum in essential tremor (ET). The aim of this study was to examine whether ET is associated with Purkinje cell (PC) loss. Prospectively categorized ET and control subjects who were longitudinally examined in the Arizona Study for Aging and Neurodegenerative Disorders and came to autopsy between 1998 and 2013 underwent standardized neuropathological assessment of the brain. PC linear density of the cerebellar hemisphere was calculated in a blinded manner. There were 56 ET cases and 62 age‐matched controls free of dementia and other neurodegenerative disorders included in the study. Mean PC linear density was 3.80 ± 0.81 cells per mm for tremor cases and 3.82 ± 0.91 cells per mm for controls (Δ 0.02; 95% confidence interval [CI]: −0.30‐0.34). PC counts were not associated with tremor duration (r = 0.06; 95% CI: −0.21‐0.32). These data demonstrate that ET is not associated with cerebellar PC loss. © 2014 International Parkinson and Movement Disorder Society
The realm of vitamin K dependent proteins: Shifting from coagulation toward calcification
Authors: Willems Brecht A. G. , Vermeer Cees , Reutelingsperger Chris P. M. , Schurgers Leon J.
Published: February 2014

In the past few decades vitamin K has emerged from a single‐function “haemostasis vitamin” to a “multi‐function vitamin.” The use of vitamin K antagonists (VKA) inevitably showed that the inhibition was not restricted to vitamin K dependent coagulation factors but also synthesis of functional extrahepatic vitamin K dependent proteins (VKDPs), thereby eliciting undesired side effects. Vascular calcification is one of the recently revealed detrimental effects of VKA. The discovery that VKDPs are involved in vascular calcification has propelled our mechanistic understanding of this process and has opened novel avenues for diagnosis and treatment. This review addresses mechanisms of VKDPs and their significance for physiological and pathological calcification.
PANDA‐T1ρ: Integrating principal component analysis and dictionary learning for fast T1ρ mapping
Authors: Zhu Yanjie , Zhang Qinwei , Liu Qiegen , Wang Yi‐Xiang J. , Liu Xin , Zheng Hairong , Liang Dong , Yuan Jing
Published: February 2014

Purpose

Long scanning time greatly hinders the widespread application of spin‐lattice relaxation in rotating frame (
) in clinics. In this study, a novel method is proposed to reconstruct the
‐weighted images from undersampled k‐space data and hence accelerate the acquisition of
imaging.

Methods

The proposed approach (PANDA‐
) combined the benefit of PCA and dictionary learning when reconstructing image from undersampled data. Specifically, the PCA transform was first used to sparsify the image series along the parameter direction and then the sparsified images were reconstructed by means of dictionary learning and finally solved the images. A variation of PANDA‐
was also developed for the heavy noise case. Numerical simulation and in vivo experiments were carried out with the accelerating factor from 2 to 4 to verify the performance of PANDA‐
.

Results

The reconstructed
maps using the PANDA‐
method were found to be comparable to the reference at all verified acceleration factors. Moreover, the variation exhibited better performance than the original version when the k‐space data were contaminated by heavy noise.

Conclusion

PANDA‐
can significantly reduce the scanning time of
by integrating PCA and dictionary learning and provides better parameter estimation than the state‐of‐art methods for a fixed acceleration factor. Magn Reson Med 73:263–272, 2015. © 2014 Wiley Periodicals, Inc.
Proton diffusion tensor spectroscopy of metabolites in human muscle in vivo
Authors: Brandejsky Vaclav , Boesch Chris , Kreis Roland
Published: February 2014

Purpose

To study the apparent diffusivity and its directionality for metabolites of skeletal muscle in humans in vivo by 1H magnetic resonance spectroscopy.

Methods

The diffusion tensors were determined on a 3 Tesla MR system using optimized acquisition and processing methods including an adapted STEAM sequence with orientation‐dependent diffusion weighting, pulse‐triggering with individually adapted delays, eddy‐current correction schemes, median filtering, and simultaneous prior‐knowledge fitting of all related spectra.

Results

The average apparent diffusivities, as well as the fractional anisotropies of taurine (ADCav = 0.74 × 10−3s/mm2, FA = 0.46), creatine (ADCav = 0.41 × 10−3 s/mm2, FA = 0.33), trimethylammonium compounds (ADCav = 0.48 × 10−3 s/mm2, FA = 0.34), carnosine (ADCav = 0.46 × 10−3 s/mm2, FA = 0.47), and water (ADCav = 1.5 × 10−3 s/mm2, FA = 0.36) were estimated. The diffusivities of most metabolites and water were significantly different from each other. Diffusion was found to be anisotropic and the diffusion tensors showed tensor correlation coefficients close to 1 and were hence found to be essentially coaligned. The magnitudes of apparent metabolite diffusivities were largely ordered according to molecular weight, with taurine as the smallest molecule diffusing fastest, both along and across the fiber direction.

Conclusion

Diffusivities, directional dependence of diffusion and fractional anisotropies of 1H MRS‐visible muscle metabolites were presented. It was shown that metabolites share diffusion directionality with water and have similar fractional anisotropies, hinting at similar diffusion barriers. Magn Reson Med 73:481–487, 2015. © 2014 Wiley Periodicals, Inc.