bluuebunny/crossref_metadata_2025 huggingface dataset:
Saitohin, which is nested within the tau gene, interacts with tau and Abl and its human‐specific allele influences Abl phosphorylation
Authors: Wang Yan , Gao Lei , Conrad Christopher G. , Andreadis Athena
Published: July 2011

Saitohin (STH) is a gene unique to humans and their closest relatives whose function is not yet known. STH contains a single polymorphism (Q7R); the Q allele is human‐specific and confers susceptibility to several neurodegenerative diseases. In previous work, we discovered that STH interacts with Peroxiredoxin 6 (Prdx6), a unique member of that family which is bifunctional and whose levels increase in Pick's disease. In this study, we report that STH also interacts with tau and the non‐receptor tyrosine kinase c‐Abl (Abl). Furthermore, Abl phosphorylates STH on its single tyrosine residue and STH increases tyrosine phosphorylation by Abl. The effect of Saitohin on Abl‐mediated phosphorylation appears to be allele‐specific, providing evidence for a new cellular function for STH. J. Cell. Biochem. 112: 3482–3488, 2011. © 2011 Wiley Periodicals, Inc.
Tissue transglutaminase promotes PDGF/PDGFR‐mediated signaling and responses in vascular smooth muscle cells
Authors: Zemskov Evgeny A. , Mikhailenko Irina , Smith Elizabeth P. , Belkin Alexey M.
Published: July 2011

Although the pivotal role of platelet derived growth factor (PDGF)‐mediated signaling in vascular diseases was demonstrated, the pathophysiological mechanisms driving its over‐activation remain incompletely understood. Tissue transglutaminase (tTG) is a multifunctional protein expressed in the vasculature, including smooth muscle cells (SMCs), and implicated in several vascular pathologies. The goal of this study is to define the regulation of PDGF‐BB/PDGFRβ‐induced signaling pathways and cell responses by tTG in vascular SMCs. We find that in human aortic SMCs, shRNA‐mediated depletion and over‐expression of tTG reveals its ability to down‐regulate PDGFRβ levels and induce receptor clustering. In these cells, tTG specifically amplifies the activation of PDGFRβ and its multiple downstream signaling targets in response to PDGF‐BB. Furthermore, tTG promotes dedifferentiation and increases survival, proliferation, and migration of human aortic SMCs mediated by this growth factor. Finally, PDGF‐BB stimulates tTG expression in human aortic SMCs in culture and in the blood vessels in response to injury. Together, our results show that tTG in vascular SMCs acts as a principal enhancer within the PDGF‐BB/PDGFRβ signaling axis involved in phenotypic modulation of these cells, thereby suggesting a novel role for this protein in the progression of vascular diseases. J. Cell. Physiol. 227: 2089–2096, 2012. © 2011 Wiley Periodicals, Inc.
Spontaneous fibroblast‐derived pericyte recruitment in a human tissue‐engineered angiogenesis model in vitro
Authors: Berthod François , Symes Julie , Tremblay Nathalie , Medin Jeffrey A. , Auger François A.
Published: July 2011

Cooperation between endothelial cells and pericytes is essential to the stabilization and maturation of blood microvessels. We developed a unique in vitro tissue‐engineered model to study angiogenesis. The human endothelialized reconstructed connective tissue model promotes the formation of a three‐dimensional branching network of capillary‐like tubes (CLT) with closed lumens. The purpose of this work was to investigate whether pericytes were spontaneously recruited around CLT in the model. We demonstrated that smooth muscle α‐actin (SMA)‐positive cells were found closely associated with PECAM‐1‐positive capillaries in the model. Twelve percent (±2.6) of SMA‐positive cells were detected along with 15% (±1.64) von Willebrand factor‐positive endothelial cells in the culture system after 31 days of in vitro maturation. Conversely, no SMA‐positive cells were detected in reconstructed connective tissues made solely of fibroblasts. Knowing that PDGF is a major factor in the recruitment of pericytes, we showed that blockade of the PDGFB receptor using the inhibitor AG1296 induced an overall 5, 2.6, and 2.4‐fold decrease in the SMA‐positive cells, von Willebrand factor‐positive cells, and number of capillaries, respectively. Using combinations of human GFP‐positive fibroblasts and endothelial cells, we demonstrated that pericytes were recruited from the fibroblast population in the model. In conclusion, our tissue‐engineered culture system promotes the spontaneous formation of a network of capillaries and the recruitment of pericytes derived from fibroblasts. Since pericytes are essential components of the blood microvasculature, this culture system is a powerful model to study angiogenesis and endothelial cell/pericyte interactions in vitro. J. Cell. Physiol. 227: 2130–2137, 2012. © 2011 Wiley Periodicals, Inc.
Safety of gadolinium‐based contrast material in sickle cell disease
Authors: Dillman Jonathan R. , Ellis James H. , Cohan Richard H. , Caoili Elaine M. , Hussain Hero K. , Campbell Andrew D. , Strouse Peter J.
Published: July 2011

Purpose:

To assess the safety of intravenously administered gadolinium‐based contrast material in sickle cell disease (SCD) patients.

Materials and Methods:

All pediatric and adult SCD patients evaluated by magnetic resonance imaging (MRI) at our institution between January 1995 and July 2009 were identified. The medical records of SCD patients who underwent contrast‐enhanced MRI as well as an equal‐sized cohort of SCD patients who underwent unenhanced MRI were reviewed for adverse (vaso‐occlusive and hemolytic) events within 1 week following imaging.

Results:

Eight (five mild and three moderate) adverse events were documented within 1 week following contrast‐enhanced MRI (38 patients and 61 contrast injections), while six (five mild and one moderate) similar events occurred within 1 week following unenhanced MRI (61 patients and 61 unenhanced MRI examinations). This difference in the number of adverse events was not statistically significant (odds ratio = 1.4; 95% confidence interval [CI] 0.4, 5.2). No severe adverse event occurred in either patient cohort.

Conclusion:

Gadolinium‐based contrast materials do not appear to be associated with increased risk of vaso‐occlusive or hemolytic adverse events when administered to SCD patients. Larger, prospective studies using multiple gadolinium‐based contrast materials would be useful to confirm the results of our investigation. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Strenuous resistance exercise effects on magnetic resonance diffusion parameters and muscle–tendon function in human skeletal muscle
Authors: Yanagisawa Osamu , Kurihara Toshiyuki , Kobayashi Naoyuki , Fukubayashi Toru
Published: July 2011

Purpose:

To assess the effects of strenuous exercise on magnetic resonance diffusion parameters and muscle–tendon complex function in skeletal muscle.

Materials and Methods:

Six men performed ankle plantar flexion exercises with eccentric contraction. The fractional anisotropy (FA), λ1, λ2, λ3, mean diffusivity (MD), and T2 values in the triceps surae muscles were measured by magnetic resonance diffusion tensor and spin‐echo imaging. Passive torque of plantar flexors, maximal voluntary isometric plantar flexion torques (MVIP), and Achilles tendon stiffness during MVIP were measured by combined ultrasonography and dynamometry. Plasma creatine kinase and muscle soreness were also assessed. These parameters were measured before and 1–8 days postexercise.

Results:

The medial gastrocnemius exhibited significantly decreased FA 2–5 days after, increased λ2 3 days after, and increased λ3 2 and 3 days after exercise. This muscle also showed significantly increased MD and T2 values 3 days postexercise. MVIP significantly decreased 2 and 3 days postexercise, while passive torque significantly increased 2 days postexercise. Creatine kinase and muscle soreness increased 3–5 days and 1–5 days postexercise, respectively.

Conclusion:

Exercise‐induced muscle damage manifested as significant changes in muscle diffusion parameters with muscle–tendon complex dysfunction and delayed‐onset muscle soreness. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Time‐resolved analysis of coronary vein motion and cross‐sectional area
Authors: Suever Jonathan D. , Watson Pierre J. , Eisner Robert L. , Lerakis Stamatios , O'Donnell Robert E. , Oshinski John N.
Published: July 2011

Purpose:

To quantify periods of low motion and cross‐sectional area changes of the coronary veins during the cardiac cycle for planning magnetic resonance coronary venograms (MRCV).

Materials and Methods:

Images were acquired from 19 patients with coronary artery disease (CAD) and 13 patients scheduled for cardiac resynchronization therapy (CRT). The displacement and cross‐sectional area of the coronary sinus was tracked, and periods of low motion were defined as consecutive time points during which the position of the coronary sinus remained within a 0.67‐mm diameter region. Patients were classified as systolic dominant or diastolic dominant based on the relative duration of their low motion periods.

Results:

All CRT patients were classified as systolic dominant, and 32% of these had no separate diastolic rest period. All CAD patients with ejection fraction < 35% were classified as systolic dominant, while all CAD patients with ejection fraction > 35%were diastolic dominant. In 77% of all subjects, the cross‐sectional area of the coronary sinus was larger in systole than in diastole.

Conclusion:

The movement of the coronary sinus can be used to classify patients as either having a longer systolic or diastolic rest period. The classification of the CRT patients as systolic dominant suggests that MRCVs be acquired in systole for CRT planning; however, each patient's low motion periods should be categorized to ensure the correct period is being used to minimize motion artifacts. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Correcting for the echo‐time effect after measuring the cerebral blood flow by arterial spin labeling
Authors: Foucher Jack R. , Roquet Daniel , Marrer Corinne , Pham Bich‐Thuy , Gounot Daniel
Published: July 2011

Purpose:

To take into account the echo time (TE) influence on arterial spin labeling (ASL) signal when converting it in regional cerebral blood flow (rCBF). Gray matter ASL signal decrease with increasing TE as a consequence of the difference in the apparent transverse relaxation rates between labeled water in capillaries and nonlabeled water in the tissue (δR). We aimed to measure ASL/rCBF changes in different parts of the brain and correct them.

Materials and Methods:

Fifteen participants underwent ASL measurements at TEs of 9.7–30 ms. Decreases in ASL values were localized by statistical parametric mapping. The corrections assessed were a subject‐per‐subject adjustment, an average δR value adjustment, and a two‐compartment model adjustment.

Results:

rCBF decreases associated with increasing TEs were found for gray matter and were corrected using an average δR value of 20 s−1. Conversely, for white matter, rCBF values increased with increasing TEs (δR = −23 s−1).

Conclusion:

Our correction was as good as using a two‐compartment model. However, it must be done separately for the gray and white matter rCBF values because the capillary R values are, respectively, larger and smaller than those of surrounding tissues. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
The application of three‐dimensional diffusion‐weighted PSIF technique in peripheral nerve imaging of the distal extremities
Authors: Chhabra Avneesh , Soldatos Theodoros , Subhawong Ty K. , Machado Antonio J. , Thawait Shrey K. , Wang Kenneth C. , Padua Abraham , Flammang Aaron J. , Williams Eric H. , Carrino John A.
Published: July 2011

Purpose:

To evaluate whether the addition of the three‐dimensional diffusion‐weighted reversed fast imaging with steady state free precession (3D DW‐PSIF) sequence improves the identification of peripheral nerves in the distal extremities.

Materials and Methods:

Twelve MR neurography (MRN) studies of the distal upper extremity and 12 MRN studies of distal lower extremity were evaluated. From the 24 subjects who were enrolled, 10 had clinically suspected peripheral neuropathy, whereas 14 suffered from various orthopedic diseases and had no clinical signs of neuropathy. In each examination, the ability to identify each peripheral nerve on T2‐weighted and 3D DW‐PSIF sequences was evaluated using a semi‐quantitative (0–2) scale. Thereafter, a total certainty score was registered for each sequence.

Results:

Combining the results of all studies, the mean certainty score was 1.92 ± 0.28 on the 3D DW‐PSIF images and 1.50 ± 0.72 on the T2‐weighted images (P < 0.001). In the upper extremity studies, the corresponding certainty scores were 2.0 and 1.70 ± 0.55, respectively (P = 0.008), and in the lower extremity studies, 1.86 ± 0.35 and 1.36 ± 0.79, respectively (P < 0.001).

Conclusion:

The 3D DW‐PSIF images provide improved identification of the nerves compared with the T2‐weighted images, and should be incorporated in the MRN protocol, whenever accurate nerve localization and/or presurgical evaluation are required. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Noncontrast‐enhanced four‐dimensional MR angiography for the evaluation of cerebral arteriovenous malformation: A preliminary trial
Authors: Xu Junling , Shi Dapeng , Chen Chuanliang , Li Yongli , Wang Meiyun , Han Xinwei , Jin Lixin , Bi Xiaoming
Published: July 2011

Purpose:

To prospectively evaluate noncontrast‐enhanced (NCE), time resolved, four‐dimensional (4D) magnetic resonance angiography (MRA) for assessment of cerebral arteriovenous malformation (AVM), with intraarterial digital subtraction angiography (DSA) performed as the reference standard.

Materials and Methods:

Fifteen patients (ten men, five women; age range 2–59 years, mean 29.4 years) with 15 untreated cerebral AVMs comprised the study population. NCE 4D MRA was performed on a 3.0 T MR scanner. MR images were reviewed by two independent readers and compared with DSA with respect to arterial feeders, nidus size, and venous drainage. Kappa coefficients of concordance were computed to determine the interobserver and intermodality agreements for the depiction of arterial feeders, nidus, and venous drainage between the two techniques.

Results:

Fifteen AVMs detected in DSA were visualized in NCE 4D MRA. Intermodality agreements were excellent for the arterial feeders (K = 0.918, P = 0.000), good for the nidus size (K = 0.692, P = 0.000), and moderate for the venous drainage (K = 0.495, P = 0.001).

Conclusion:

NCE 4D MRA is a promising and potentially valuable method for noninvasive assessment of angioarchitecture and hemodynamics of cerebral AVMs. Further improvement of labeling persistence is desirable in order to enhance the depiction of draining veins for AVMs. J. Magn. Reson. Imaging 2011;. © 2011 Wiley Periodicals, Inc.
Reproducibility of MRI‐determined proton density fat fraction across two different MR scanner platforms
Authors: Kang Geraldine H. , Cruite Irene , Shiehmorteza Masoud , Wolfson Tanya , Gamst Anthony C. , Hamilton Gavin , Bydder Mark , Middleton Michael S. , Sirlin Claude B.
Published: July 2011

Purpose:

To evaluate magnetic resonance imaging (MRI)‐determined proton density fat fraction (PDFF) reproducibility across two MR scanner platforms and, using MR spectroscopy (MRS)‐determined PDFF as reference standard, to confirm MRI‐determined PDFF estimation accuracy.

Materials and Methods:

This prospective, cross‐sectional, crossover, observational pilot study was approved by an Institutional Review Board. Twenty‐one subjects gave written informed consent and underwent liver MRI and MRS at both 1.5T (Siemens Symphony scanner) and 3T (GE Signa Excite HD scanner). MRI‐determined PDFF was estimated using an axial 2D spoiled gradient‐recalled echo sequence with low flip‐angle to minimize T1 bias and six echo‐times to permit correction of T2* and fat‐water signal interference effects. MRS‐determined PDFF was estimated using a stimulated‐echo acquisition mode sequence with long repetition time to minimize T1 bias and five echo times to permit T2 correction. Interscanner reproducibility of MRI determined PDFF was assessed by correlation analysis; accuracy was assessed separately at each field strength by linear regression analysis using MRS‐determined PDFF as reference standard.

Results:

1.5T and 3T MRI‐determined PDFF estimates were highly correlated (r = 0.992). MRI‐determined PDFF estimates were accurate at both 1.5T (regression slope/intercept = 0.958/‐0.48) and 3T (slope/intercept = 1.020/0.925) against the MRS‐determined PDFF reference.

Conclusion:

MRI‐determined PDFF estimation is reproducible and, using MRS‐determined PDFF as reference standard, accurate across two MR scanner platforms at 1.5T and 3T. J. Magn. Reson. Imaging 2011;. © 2011 Wiley‐Liss, Inc.
Screening and rank ordering of reversible mechanism‐based inhibitors of Hepatitis C virus NS3 protease using electrospray ionization mass spectrometry
Authors: Liu Yan‐Hui , Ramanathan Lata , Malcolm Bruce , Njoroge George , Chan Tin‐Yau , Pramanik Birendra N.
Published: July 2011

An affinity‐selection study using size exclusion chromatography (SEC) combined with off‐line electrospray ionization mass spectrometry (ESI‐MS) was performed on libraries of peptidic α‐ketoamide inhibitors directed against the hepatitis C virus (HCV) NS3 protease. A limiting amount of HCV NS3 protease (25 µM) was incubated with equimolar amounts (100 µM) of 49 reversible mechanism‐based ketoamide inhibitors, previously grouped into seven sets to ensure clearly distinguishable mass differences of the enzyme‐inhibitor complexes (>10 Da). The unbound compounds were separated rapidly from the protease and the protease‐inhibitor complexes by SEC spin columns. The eluate of the SEC was immediately analyzed by direct‐infusion ESI‐MS. An enzyme‐inhibitor complex, with a molecular mass corresponding to the NS3 protease binding to the preferred inhibitor, SCH212986, was the only molecular species detected. By increasing the molar ratio of HCV NS3 protease to inhibitors to 1:2 while keeping the inhibitors' concentration constant, the complex of the second most tightly bound inhibitor, SCH215426, was also identified. Although the potencies of these inhibitors were virtually un‐measurable by kinetic assays, a rank order of CVS4441 > SCH212986 > SCH215426 was deduced for their inhibition potencies by direct competition experiment with CVS4441 ($K_{\rm {i}}^* > 80 \mu$ M). As discussed in the article, through judicious application of this strategy, even large libraries of fairly weak, reversible and slow‐binding inhibitors could be rapidly screened and rank ordered to provide critical initial structure‐activity insights. Copyright © 2011 John Wiley & Sons, Ltd.
Molecular evidence for maternal inheritance of the chloroplast genome in tea, Camellia sinensis (L.) O. Kuntze
Authors: Kaundun Shiv Shankhar , Matsumoto Satoru
Published: July 2011

BACKGROUND: Tea is the most consumed beverage worldwide after water. Yet very little is known about the genetics of tea in comparison with other crop species. Here we have taken advantage of the polymorphic nature of microsatellite DNA to investigate the mode of chloroplast inheritance in tea, Camellia sinensis (L.) O. Kuntze. This is important for the correct interpretation of phylogeny and introgression data as well as assessing the suitability of chloroplast transformation as a means for transgene containment in tea.

RESULTS: The study was based on six Japanese tea cultivars, namely Aj2, CK23, Hatsumomiji, Nka05, Yamanoibuki and Kanayamidori used to generate four informative families. The parental pairs in the crosses differed at a single chlroroplast locus with respect to an imperfect microsatellite repeat of 16 nucleotide bases. In agreement with earlier cytological studies, all 61 progeny displayed a cpDNA profile that was consistent with the maternal inheritance of chloroplasts in tea.

CONCLUSIONS: The data generated here provide the first molecular evidence of the plastid inheritance in tea. However, we suggest that additional families and polymorphic markers be screened for increasing the confidence in the observed maternal inheritance of chloroplasts in this important crop species. Copyright © 2011 Society of Chemical Industry
Integrating crops and livestock in subtropical agricultural systems
Authors: Wright Iain A , Tarawali Shirley , Blümmel Michael , Gerard Bruno , Teufel Nils , Herrero Mario
Published: July 2011

As the demand for livestock products increases, and is expected to continue to increase over the next few decades, especially in developing countries, smallholder mixed systems are becoming more intensive. However, with limited land and water resources and concern about the environmental impact of agricultural practices and climate change, the challenge is to find ways of increasing productivity that do not compromise household food security, but rather increase incomes equitably and sustain or enhance the natural resource base. In developed countries there has been increased specialisation of crop and livestock production. In contrast, the majority of livestock in developing countries is kept in mixed crop/livestock systems. Crops (cereal grains and pulses) and crop residues provide the basis of the diet for animals, e.g. cereal straw fed to dairy cattle or sweet potato vines fed to pigs. Animal manure can provide significant nutrient inputs to crops. Water productivity is higher in mixed crop/livestock systems compared with growing crops alone. Mixed systems allow for a more flexible and profitable use of family labour where employment opportunities are limited. They also spread risks across several enterprises, a consideration in smallholder systems that may become even more important under certain climate change scenarios. Integrated crop/livestock systems can play a significant role in improving global food security but will require appropriate technological developments, institutional arrangements and supportive policy environments if they are to fulfil that potential in the coming decades. Copyright © 2011 Society of Chemical Industry
Salt marsh harvest mouse demography and habitat use in the Suisun Marsh, California
Authors: Sustaita Diego , Quickert Patty Finfrock , Patterson Laura , Barthman‐Thompson Laureen , Estrella Sarah
Published: July 2011

We undertook a 2‐year (2002–2004) mark–recapture study to investigate demographic performance and habitat use of salt marsh harvest mice (Reithrodontomys raviventris halicoetes) in the Suisun Marsh. We examined the effects of different wetland types and microhabitats on 3 demographic variables: density, reproductive potential, and persistence. Our results indicate that microhabitats dominated by mixed vegetation or pickleweed (Salicornia spp.) supported similar salt marsh harvest mouse densities, reproductive potential, and persistence throughout much of the year, whereas few salt marsh harvest mice inhabited upland grass‐dominated microhabitats. We found that densities were higher in diked wetlands, whereas post‐winter persistence was higher in tidal wetlands, and reproductive potential did not differ statistically between wetland types. Our results emphasize the importance of mixed vegetation for providing adequate salt marsh harvest mouse habitat and suggest that, despite their physiognomic and hydrological differences, both diked and tidal wetlands support salt marsh harvest mouse populations by promoting different demographic attributes. We recommend that habitat management, restoration, and enhancement efforts include areas containing mixed vegetation in addition to pickleweed in both diked and tidal wetlands. © 2011 The Wildlife Society.
Effects of predator treatments, individual traits, and environment on moose survival in Alaska
Authors: Keech Mark A. , Lindberg Mark S. , Boertje Rodney D. , Valkenburg Patrick , Taras Brian D. , Boudreau Toby A. , Beckmen Kimberlee B.
Published: July 2011

We studied moose (Alces alces) survival, physical condition, and abundance in a 3‐predator system in western Interior Alaska, USA, during 2001–2007. Our objective was to quantify the effects of predator treatments on moose population dynamics by investigating changes in survival while evaluating the contribution of potentially confounding covariates. In May 2003 and 2004, we reduced black bear (Ursus americanus) and brown bear (U. arctos) numbers by translocating bears ≥240 km from the study area. Aircraft‐assisted take reduced wolf (Canis lupus) numbers markedly in the study area during 2004–2007. We estimated black bears were reduced by approximately 96% by June 2004 and recovered to within 27% of untreated numbers by May 2007. Brown bears were reduced approximately 50% by June 2004. Late‐winter wolf numbers were reduced by 75% by 2005 and likely remained at these levels through 2007. In addition to predator treatments, moose hunting closures during 2004–2007 reduced harvests of male moose by 60% in the study area. Predator treatments resulted in increased calf survival rates during summer (primarily from reduced black bear predation) and autumn (primarily from reduced wolf predation). Predator treatments had little influence on survival of moose calves during winter; instead, calf survival was influenced by snow depth and possibly temperature. Increased survival of moose calves during summer and autumn combined with relatively constant winter survival in most years led to a corresponding increase in annual survival of calves following predator treatments. Nonpredation mortalities of calves increased following predator treatments; however, this increase provided little compensation to the decrease in predation mortalities resulting from treatments. Thus, predator‐induced calf mortality was primarily additive. Summer survival of moose calves was positively related to calf mass (β > 0.07, SE = 0.073) during treated years and lower (β = −0.82, SE = 0.247) for twins than singletons during all years. Following predator treatments, survival of yearling moose increased 8.7% for females and 21.4% for males during summer and 2.2% for females and 15.6% for males during autumn. Annual survival of adult (≥2 yr old) female moose also increased in treated years and was negatively (β = −0.21, SE = 0.078) related to age. Moose density increased 45%, from 0.38 moose/km2 in 2001 to 0.55 moose/km2 in 2007, which resulted from annual increases in overall survival of moose, not increases in reproductive rates. Indices of nutritional status remained constant throughout our study despite increased moose density. This information can be used by wildlife managers and policymakers to better understand the outcomes of predator treatments in Alaska and similar environments. © 2011 The Wildlife Society.
SOIL PROPERTY CHANGES FOLLOWING IRRIGATION WITH COALBED NATURAL GAS WATER: ROLE OF WATER TREATMENTS, SOIL AMENDMENTS AND LAND SUITABILITY
Authors: Johnston C. R. , Vance G. F. , Ganjegunte G. K.
Published: July 2011

Saline‐sodic water is a by‐product of coalbed natural gas (CBNG) production in the Powder River Basin of Wyoming, USA and is being beneficially used in places as irrigation water. This study evaluated effects of 2 years of natural precipitation on soil properties of a hay field after the cessation of managed irrigation with CBNG water. The hay field had been irrigated with only CBNG water [CBNG(NT)], CBNG water amended with gypsum [CBNG(G)] or gypsum plus sulfur via a sulfur burner [CBNG(GSB)] in combination with soil amendments—gypsum (+G), elemental sulfur (+S), and both (+GS). Results indicated that infiltration rates were the lowest on fields irrigated with CBNG(NT), followed by CBNG(G) and CBNG(NT)+G treatments (12·2, 13·2, and 13·5 cm h−1, respectively). The CBNG(GSB)+GS treatment had the highest infiltration rates (33·5 cm h−1). By the second year, salinity and sodicity of treated soils had decreased in the A‐horizon of most CBNG‐water irrigated plots, whereas in Bt1‐ and Bt2‐horizons salinity generally decreased but sodicity increased; S and GS soil amended plots had higher profile salinities compared with NT and G soil treatments. Although Na+ leaching was observed in all fields that received soil and/or water amendments, CBNG(GSB)+GS plots had the lowest sodicity in the A‐ and Bt1‐horizons. Effective managed irrigation requires knowledge of site‐specific soil properties, plant suitability, water chemistry, and amendments that would be needed to treat the CBNG waters and soils. This study indicates the greatest success was realized when using both soil and water amendments. Copyright © 2011 John Wiley & Sons, Ltd.
Changing picture of central nervous system complications in liver transplant recipients
Authors: Vizzini Giovanni , Asaro Monica , Miraglia Roberto , Gruttadauria Salvatore , Filì Daniela , D'Antoni Adele , Petridis Ioannis , Marrone Gianluca , Pagano Duilio , Gridelli Bruno
Published: July 2011

Central nervous system (CNS) complications are common after liver transplantation (LT). According to the literature, the most common causes are infections and the neurotoxicity of immunosuppressive drugs (cyclosporine and tacrolimus). The aim of this study was to evaluate the incidence, clinical presentations, etiologies, and outcomes of CNS complications in a series of 395 consecutive LT recipients whose immunosuppression regimen was designed for low tacrolimus blood levels. An analysis of the 12-hour trough concentrations of tacrolimus in the study population showed that the target drug levels, which were designed to maintain minimal immunosuppression, were usually achieved. In all, 64 patients (16.2%) developed major neurological symptoms (37 within 30 days of LT). None of the observed CNS complications were caused by infections (viral, bacterial, or fungal), and only 3 of the 395 patients (0.8%) received a diagnosis of tacrolimus-related leukoencephalopathy. Cerebrovascular disease was identified in 15 patients (3.8%; 8 had cerebral hemorrhages, 5 had ischemic strokes, and 2 had subdural hemorrhages). Pontine myelinolysis was found in 2 patients (0.5%). Notably, no clear cause was identified for the remaining 44 cases (11.1%): brain imaging was negative for 22 cases, and diffuse hypoxic changes were present for the other 22. CNS complications were significantly associated with a reduction in 3-month patient survival (88.8% versus 95.4%) and 5-year patient survival (57.3% versus 84.1%). Among the pretransplant variables that were analyzed, the incidence of portosystemic encephalopathy, the peak serum bilirubin levels, and the lowest serum total cholesterol levels were significantly different between the 64-patient group with CNS complications and the asymptomatic group of 331 patients.
Cost of a quality-adjusted life year in liver transplantation: The influence of the indication and the model for end-stage liver disease score
Authors: Åberg Fredrik , Mäklin Suvi , Räsänen Pirjo , Roine Risto P. , Sintonen Harri , Koivusalo Anna-Maria , Höckerstedt Krister , Isoniemi Helena
Published: July 2011

Cost issues in liver transplantation (LT) have received increasing attention, but the cost-utility is rarely calculated. We compared costs per quality-adjusted life year (QALY) from the time of placement on the LT waiting list to 1 year after transplantation for 252 LT patients and to 5 years after transplantation for 81 patients. We performed separate calculations for chronic liver disease (CLD), acute liver failure (ALF), and different Model for End-Stage Liver Disease (MELD) scores. For the estimation of QALYs, the health-related quality of life was measured with the 15D instrument. The median costs and QALYs after LT were €141,768 and 0.895 for 1 year and €177,618 and 3.960 for 5 years, respectively. The costs of the first year were 80% of the 5-year costs. The main cost during years 2 to 5 was immunosuppression drugs (59% of the annual costs). The cost/QALY ratio improved from €158,400/QALY at 1 year to €44,854/QALY at 5 years, and the ratio was more beneficial for CLD patients (€42,500/QALY) versus ALF patients (€63,957/QALY) and for patients with low MELD scores versus patients with high MELD scores. Although patients with CLD and MELD scores > 25 demonstrated markedly higher 5-year costs (€228,434) than patients with MELD scores < 15 (€169,541), the cost/QALY difference was less pronounced (€59,894/QALY and €41,769/QALY, respectively). The cost/QALY ratio for LT appears favorable, but it is dependent on the assessed time period and the severity of the liver disease.
2‐Methoxyestradiol induced bax phosphorylation and apoptosis in human retinoblastoma cells via p38 MAPK activation
Authors: Min Hongbo , Ghatnekar Gautam S. , Ghatnekar Angela V. , You Xiaohong , Bu Min , Guo Xinyi , Bu Shizhong , Shen Bo , Huang Qin
Published: July 2011

Retinoblastoma (Rb) is a common childhood intraocular cancer that affects approximately 300 children each year in the United States alone. 2‐Methoxyestradiol (2ME), an endogenous metabolite of 17‐β‐estradiol that dose not bind to nuclear estrogen receptor, exhibits potent apoptotic activity against rapidly growing tumor cells. Here, we report that 2ME induction of apoptosis was demonstrated by early fragmented DNA after 48 h of incubation with 10 µM 2ME in Rb cell lines. Subsequently, a decrease of proliferation was observed in a time‐ and dose‐dependent manner. Further analysis of the mechanism indicates that p38 kinase plays a critical role in 2ME‐induced apoptosis in Y79 cells, even though ERK was also activated by 2ME under the same conditions. Activation of p38 kinase also mediates 2ME induced Bax phosphorylated at Thr167 after a 6 h treatment of 2ME, which in turn prevents formation of the Bcl‐2‐Bax heterodimer. Both p38 specific inhibitor, SB 203580, or p38 knockdown by specific siRNA, blocked 2ME induction of Bax phosphorylation. Furthermore, only transiently transfected mutant BaxT167A, but not Bax S163A, inhibited 2ME‐induced apoptosis. In summary, our data suggest that 2ME induces apoptosis in human Rb cells by causing phosphorylation of p38 Mitogen‐activated protein kinase (MAPK), which appears to be correlated with phosphorlation of Bax. This understanding of 2ME's ability may help develop it as a promising therapeutic candidate by inducing apoptosis in a Rb. © 2011 Wiley Periodicals, Inc.
Finite strain analysis of nonuniform deformation inside shear bands in sands
Authors: Chupin O. , Rechenmacher A. L. , Abedi S.
Published: July 2011

A methodology has been developed to extend the incremental (Eulerian) Digital Image Correlation (DIC) technique to enable a Lagrangian‐based large‐strain analysis framework to examine the nature of strain and kinematic nonuniformity within shear bands in sands. Plane strain compression tests are performed on dense sands in an apparatus that promotes unconstrained persistent shear band formation. DIC is used to capture incremental, grain‐scale displacements in and around shear bands. The performance of the developed accumulation algorithm is validated by comparing accumulated displacements with two sources of reference measurements. A comparison between large and infinitesimal rotation is performed, demonstrating the nature of straining within shear bands in sands and the necessity of using a finite strain formulation to characterize ensuing behavior. Volumetric strain variation along the shear band is analyzed throughout macroscopic postpeak deformation. During softening, volumetric activity within the shear band is purely dilative. During the global critical state, the shear band material is seen on the average to deform at zero volumetric strain; however, locally, the sand is seen to exhibit significant nonzero volumetric strain, putting into question the current definition of critical state. At the softening‐critical state transition, a spatially periodic pattern of alternating contraction and dilation along the shear band is evidenced, and a preliminary evaluation indicates that the periodicity appears to be a physical phenomenon dictated only in part by median grain size. Copyright © 2011 John Wiley & Sons, Ltd.
Rate‐enhanced ATRP in the presence of catalytic amounts of base: An example of iron‐mediated AGET ATRP of MMA
Authors: Bai Liangjiu , Zhang Lifen , Zhang Zhengbiao , Zhu Jian , Zhou Nianchen , Cheng Zhenping , Zhu Xiulin
Published: July 2011

The catalytic amount of inorganic bases (i.e., NaOH, Na3PO4, NaHCO3, and Na2CO3) and organic bases such as pyridine and triethylamine was used as the additives in an iron‐mediated atom transfer radical polymerization with activators generated by electron transfer (AGET ATRP) of a polar monomer methyl methacrylate (MMA) using FeCl3·6H2O as the catalyst, ethyl 2‐bromoisobutyrate (EBiB) as the initiator, ascorbic acid (AsAc) as the reducing agent, and tetrabutylammonium bromide (TBABr) as the ligand. All these bases can result in dual enhancement of polymerization rate and controllability over molecular weight while keeping low Mw/Mn values (<1.3) for the resultant polymers. For example, the polymerization rate of AGET ATRP with a molar ratio of [MMA]0/[EBiB]0/[FeCl3·6H2O]0/[TBABr]0/[AsAc]0/[NaOH]0 = 500/1/1/2/2/1.5 using NaOH as the additives was more than two times of that without NaOH. The nature of “living”/controlled free radical polymerization in the presence of base was confirmed by chain‐extension experiments. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
A thioxanthone‐based visible photoinitiator
Authors: Dogruyol Sevnur Keskin , Dogruyol Zekeriya , Arsu Nergis
Published: July 2011

Thioxanthone‐based 9‐(2‐Morpholine‐4yl‐acetyl)‐5‐thia‐napthasen‐12‐one (TX‐MPM) was synthesized and characterized as a one‐component novel visible photoinitiator. Its capability to act as an initiator for the polymerization of methyl methacrylate (MMA) was examined in photoreactor and also daylight. Photophysical properties: fluorescence and phosphorescence emission spectra and fluorescence quantum yield of TX‐MPM (ϕf = 0.29) were determined. The phosphorescence lifetime was found 131 ms for TX‐MPM and 110 ms for initiator‐attached polymer (PMMA) at 77 K, indicated a π→π* nature of the lowest triplet state. A model compound, morpholino acetonapthone was used as quencher for the triplet states of TX‐MPM and the quenching rate constant was determined (kq = 1.26 × 109 M−1s−1). According to laser flash photolysis studies, intermolecular hydrogen abstraction process was more dominant path to the formation of the initiating radicals. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Molten polystyrene structures above the glass transition, T > Tg
Authors: Utracki L. A. , Sammut P.
Published: July 2011

The old controversial idea of structures in molten amorphous polymers is being accepted with theoretical and experimental evidence. Wool's twinkling fractal theory of the glass transition and recent atomic force micrographs are convincing proof of the dynamic, solid aggregate presence below and above Tg. This article offers detailed analysis of the experimental data from high‐pressure dilatometry, as well as from the oscillatory shear tests in the glassy and the molten state of polystyrenes. The results indicate the presence of a transient structure at T > Tg; transient as it depends on the structure of the vitreous polymer and the rate of heating it across Tg. Thus, molten polymer is not always at the thermodynamic equilibrium. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1369–1380, 2011
Predictors of follow‐up exercise behavior 6 months after a randomized trial of supervised exercise training in lymphoma patients
Authors: Courneya Kerry S. , Stevinson Clare , McNeely Margaret L. , Sellar Christopher M. , Friedenreich Christine M. , Peddle‐McIntyre Carolyn J. , Chua Neil , Reiman Tony
Published: July 2011

Objectives

Supervised exercise is beneficial for lymphoma patients, but it needs to be maintained to optimize long‐term benefits. Here, we report the predictors of follow‐up exercise behavior 6 months after a randomized controlled trial in lymphoma patients.

Methods

Lymphoma patients were randomly assigned to 12 weeks of supervised aerobic exercise (n = 60) or usual care (n = 62). At baseline and post‐intervention, data were collected on demographic, medical, health‐related fitness, quality of life, and motivational variables. At 6‐month follow‐up, participants were mailed a questionnaire that assessed exercise behavior and were categorized as meeting or not meeting public health exercise guidelines.

Results

At 6‐month follow‐up, 110 participants (90.2%) responded, of which 61 (55.5%) were meeting public health exercise guidelines. In univariate analyses, 16 variables predicted 6‐month follow‐up exercise behavior. In a stepwise regression analysis, five variables entered the model and explained 38% (p < 0.001) of the variance including the following: accepting a post‐intervention exercise prescription (β = 0.33; p < 0.001), achieving a higher peak power output at post‐intervention (β = 0.28; p = 0.001), experiencing a larger positive change in perceived behavioral control (β = 0.18; p = 0.028), having Hodgkin lymphoma (β = 0.19; p = 0.025), and having a stronger post‐intervention intention (β = 0.18; p = 0.034).

Conclusion

Exercise behavior in lymphoma patients 6 months after a randomized trial was predicted by a wide range of demographic, medical, health‐related fitness, quality of life, and motivational variables. These findings may help facilitate the uptake of self‐directed exercise after short‐term supervised exercise in lymphoma patients. Copyright © 2011 John Wiley & Sons, Ltd.
Information about chemotherapy‐associated cognitive problems contributes to cognitive problems in cancer patients
Authors: Schagen Sanne B. , Das Enny , Vermeulen Ivar
Published: July 2011

Objective

Although increasing attention is directed at identifying biological mechanisms underlying cognitive changes observed in cancer patients without central nervous system disease following chemotherapy, psychological factors that can contribute to these cognitive changes are much less studied.

Methods

In an online experiment, the influence of informing patients about the association between cognitive problems and chemotherapy on self‐reported cognitive functioning and neuropsychological test performance was investigated.

Results

Cancer patients treated with chemotherapy (n = 150) reported higher levels of cognitive complaints after receiving such information (M = 21.20) than without such information (M = 18.98; p = 0.032). No difference was found for patients without (a history of) chemotherapy (n = 86; M = 18.85 vs. 20.08; NS). A similar interaction pattern was observed on a word‐learning test. Patients treated with chemotherapy recalled fewer words after being informed about the association between cognitive problems and chemotherapy (M = 24.44) than without such information (M = 27.63; p = 0.010). No difference was found for patients not treated with chemotherapy (M = 26.35 vs. 25.38; NS).

Conclusion

Patient information may induce a stereotype threat, which affects self‐reported cognitive function and neuropsychological test performance in cancer patients for whom this information is relevant. Copyright © 2011 John Wiley & Sons, Ltd.
Dirac gauginos: a user manual
Authors: Benakli K.
Published: July 2011

The issue of a Majorana, Dirac or pseudo‐Dirac mass for gauginos must not be reduced to a question of an extension of the Minimal Supersymmetric Standard Model by extra states, parameters and phenomenological implications. On the contrary, it is intimately related to the fundamental issue of the realization of new symmetries in nature, R‐symmetries. We present here a very dense compilation of the main features of models with (pseudo‐)Dirac gauginos.
Enhancing systematic protein–protein docking methods using ray casting: Application to ATTRACT
Authors: Li Yi , Cortés Juan , Siméon Thierry
Published: July 2011

Systematic protein–protein docking methods need to evaluate a huge number of different probe configurations, thus leading to high computational cost. We present an efficient filter—ray casting filter (RCF)—that enables a notable speed‐up of systematic protein–protein docking. The high efficiency of RCF is the outcome of the following factors: (i) extracting of pockets and protrusions on the surfaces of the proteins using visibilities; (ii) a ray casting method that finds aligned receptor pocket/probe protrusion pairs without explicit similarity computations. The RCF method enables the integration of systematic methods and local shape feature matching methods. To verify the efficiency and the accuracy of RCF, we integrated it with a systematic protein–protein docking approach (ATTRACT) based on a reduced protein representation. The test results show that the integrated docking approach is much faster. At the same time, it ranks the lowest ligand root‐mean‐square deviation (RMSD) (L_rms) solutions higher when docking enzyme–enzyme inhibitor complexes. Consequently, RCF not only enables much faster execution of systematic docking runs but also improves the qualities of docking predictions. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Further studies on the antiviral activity of alloferon and its analogues
Authors: Kuczer Mariola , Midak‐Siewirska Anna , Zahorska Renata , Łuczak Mirosław , Konopińska Danuta
Published: July 2011

The subject of our studies was the synthesis, biological evaluation, and conformational studies of insect tridecapeptide alloferon (H‐His‐Gly‐Val‐Ser‐Gly‐His‐Gly‐Gln‐His‐Gly‐Val‐His‐Gly‐OH) and its analogues such as: [des‐His1]‐, [Lys1]‐, [Arg1]‐, and [Ala1]‐alloferon. These peptides were synthesized to check the influence of the His residue at position 1 of the alloferon chain on its antiviral activity. Two aspects of the biological effects of these peptides were determined: (i) the cytotoxicity in vitro in the Vero, LLC‐MK2, and HEp‐2 cell lines, and (ii) the antiviral activity in vitro in respect to DNA and RNA viruses. We found that alloferon inhibited the herpes virus multiplication and failed to affect the coxsackie virus replication, whereas [Lys1]‐alloferon exhibited a high inhibitory action towards both viruses. Moreover, the peptides did not show any cytotoxic activity against the Vero, LLC‐MK2, and HEp‐2 cells. The preliminary circular dichroism conformational studies showed that the peptides investigated seem to prefer an unordered conformation. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.
Total synthesis of a depsidomycin analogue by convergent solid‐phase peptide synthesis and macrolactonization strategy for antitubercular activity
Authors: Narayanaswamy Venugopala K. , Albericio Fernando , Coovadia Yacoob Mohamed , Kruger Hendrik G. , Maguire Glenn E. M. , Pillay Melendhran , Govender Thavendran
Published: July 2011

Depsidomycin is a cyclic heptadepsi‐peptide isolated from the cultured broth of Streptomyces lavendofoliae MI951‐62F2. It exhibits significant antimicrobial and immunosuppressive activity. The total synthesis of a depsidomycin analogue in which 1,2‐piperazine‐3‐carboxylic acid was substituted with proline is described. After several trials using different strategies, the desired depsidomycin analogue was obtained via stepwise synthesis starting by the amino acid ‘head’ and macrolactonization under Yamaguchi conditions. The cyclic depsipeptide was evaluated to have an minimum inhibitory concentration (MIC) of 4 µg/ml against H37RV and 16 µg/ml against MDR clinical strains of MTB (MDR‐MTB), while the linear precursor 8 also had MICs of 4 and 16 µg/ml for the susceptible and resistant strains, respectively. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.
A theoretical study on hydrogen transport mechanism in SrTio3 perovskite
Authors: Onishi Taku , Helgaker Trygve
Published: July 2011

Hybrid‐DFT calculations were performed to clarify the hydrogen transport mechanism in SrTiO3 perovskite. From a molecular‐orbital analysis, we discussed the changes of the chemical bonding between conductive hydrogen and others, and the proton conduction paths. It is concluded that the conductive hydrogen is almost neutral, with a diagonal conduction path favored inside of Ti4O4 square. We considered the nitrogen doping at the oxygen site to enhance the proton conductivity. Doped nitrogen exists as the part of NH2− ion, enhancing proton conductivity. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012