bluuebunny/crossref_metadata_2025 huggingface dataset:
Topology for current balancer with half‐bridge inverters in single‐phase three‐wire distribution systems with DC‐capacitor‐voltage balancer
Authors: Baba Yusuke , Sugahara Kazuya , Okamoto Masayuki , Hiraki Eiji , Tanaka Toshihiko
Published: June 2012

This paper proposes a new topology for a current balancer with half‐bridge inverters in single‐phase three‐wire distribution systems. Two half‐bridge inverters are connected to the sources. The midpoint of the two capacitors on the DC‐side is connected to a neutral line. The two half‐bridge inverters function as a current balancer for single‐phase three‐wire distribution systems by exchanging the active and reactive power on each feeder through the two DC capacitors. The third leg functions as a DC‐capacitor‐voltage balancer for two DC capacitors connected to the half‐bridge inverters. Thus, balanced source voltages and currents are obtained on the secondary side on the pole‐ mounted distribution transformer with balanced DC‐capacitor voltages. The basic principle of the proposed current balancer is discussed in detail, and then confirmed by digital computer simulation using PSIM software. A prototype experimental model is constructed and tested. Experimental results show that balanced source voltages and currents are obtained on the secondary side on the pole‐mounted distribution transformer with balanced DC‐capacitor voltages. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(4): 38–46, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22277
A polyphenol extract of tara pods (Caesalpinia spinosa) as a potential antioxidant in oils
Authors: Romero Nalda , Fernández Arturo , Robert Paz
Published: June 2012

Tara is a native species of Peru and is widely distributed in Latin America; its fruits (pods) have a high potential for medical, industrial and food uses. A supercritical tara polyphenol extract (STPE) was obtained from tara pods by supercritical fluid extraction (SFE) with CO2. The antioxidant activity of the STPE was studied in two oils, regular and high‐oleic sunflower oil (SO, HOSO), with and without their natural antioxidants. Under accelerated conditions of oxidation, a linear relationship was observed in antioxidant‐stripped oils between the polyphenol content of the STPE and the induction period.

The antioxidant effect of STPE on the HOSO was studied at 60°C. The highest polyphenol concentration of STPE showed the greatest α‐tocopherol degradation and the lowest hydroperoxide formation, which implies that α‐tocopherol causes the regeneration of the polyphenols that protect the TAGs in HOSO.

Tara pods combined with SFE method could be used as a source of antioxidants in oils.
Response of base‐isolated nuclear structures for design and beyond‐design basis earthquake shaking
Authors: Huang Yin‐Nan , Whittaker Andrew S. , Kennedy Robert P. , Mayes Ronald L.
Published: June 2012

The American Society of Civil Engineers (ASCE) 43‐05 presents two performance objectives for the design of nuclear structures, systems and components in nuclear facilities: (1) 1% probability of unacceptable performance for 100% design basis earthquake (DBE) shaking and (2) 10% probability of unacceptable performance for 150% DBE shaking. To aid in the revision of the ASCE 4‐98 procedures for the analysis and design of base‐isolated nuclear power plants and meet the intent of ASCE 43‐05, a series of nonlinear response‐history analyses was performed to study the impact of the variability in both earthquake ground motion and mechanical properties of isolation systems on the seismic responses of base‐isolated nuclear power plants. Computations were performed for three representative sites (rock and soil sites in the Central and Eastern United States and a rock site in the Western United States) and three types of isolators (lead rubber, Friction Pendulum and low‐damping rubber bearings) using realistic mechanical properties for the isolators. Estimates were made of (1) the ratio of the 99th percentile (90th percentile) response of isolation systems computed using a distribution of spectral demands and distributions of isolator mechanical properties to the median response of isolation systems computed using best‐estimate properties and 100% (150%) spectrum‐compatible DBE ground motions; (2) the number of sets of three‐component ground motions to be used for response‐history analysis to develop a reliable estimate of the median response of isolation systems. The results of this study provide the technical basis for the revision of ASCE Standard 4‐98. Copyright © 2012 John Wiley & Sons, Ltd.
Brain tissue modifications induced by cholinergic therapy in Alzheimer's disease
Authors: Bozzali Marco , Parker Geoff J.M. , Spanò Barbara , Serra Laura , Giulietti Giovanni , Perri Roberta , Magnani Giuseppe , Marra Camillo , G.Vita Maria , Caltagirone Carlo , Cercignani Mara
Published: June 2012

A previous preliminary investigation based on a novel MRI approach to map anatomical connectivity revealed areas of increased connectivity in Alzheimer's disease (AD) but not in mild cognitive impairment patients. This prompted the hypothesis tested here, that these areas might reflect phenomena of brain plasticity driven by acetylcholinesterase inhibitors (AChEIs). Thirty‐eight patients with probable AD (19 under medication with AChEIs and 19 drug‐naïve) were recruited together with 11 healthy controls. All subjects had MRI scanning at 3T, including volumetric and diffusion‐weighted scans. Probabilistic tractography was used to initiate streamlines from all parenchymal voxels, and anatomical connectivity maps (ACMs) were obtained by counting, among the total number of streamlines initiated, the fraction passing through each brain voxel. After normalization into standard space, ACMs were used to test for between‐group comparisons, and for interactions between the exposure to AChEIs and global level of cognition. Patients with AD had reduced ACM values in the fornix, cingulum, and supramarginal gyri. The ACM value was strongly associated with the AChEI dosage‐x‐duration product in the anterior limb (non‐motor pathway) of the internal capsule. Tractography from this region identified the anterior thalamic radiation as the main white matter (WM) tract passing through it. The reduced connectivity in WM bundles connecting the hippocampi with the rest of the brain (fornix/cingulum) suggests a possible mechanism for the spread of AD pathology. An intriguing explanation for the interaction between AChEIs and ACM is related to the mechanisms of brain plasticity, partially driven by neurotrophic properties of acetylcholine replacement. Hum Brain Mapp 34:3158–3167, 2013. © 2012 Wiley Periodicals, Inc.
Generation of precursor cell lines from preneoplastic fields surrounding head and neck cancers
Authors: van Zeeburg Hester J.T. , Graveland A. Peggy , Brink Arjen , Nguyen Melanie , Leemans C. René , Bloemena Elisabeth , Braakhuis Boudewijn J.M. , Brakenhoff Ruud H.
Published: June 2012

Background

Head and neck squamous cell carcinoma (HNSCC) develops in the mucosal linings of the upper aerodigestive tract. HNSCC may develop in large preneoplastic fields, which are in most cases invisible, but can be detected microscopically and by genetic analysis.

Methods

Cells of mucosal tissue biopsies were cultured and genetically analyzed. Genetic changes in established preneoplastic cultures were compared to the corresponding tumor and surgical margins.

Results

Of 45 mucosal tissue biopsies taken from primary tumor resection specimen, 26 were successfully cultured and could be genetically analyzed. In 1 culture, genetic changes were found and an immortalized preneoplastic cell line was obtained with genetic changes that were also found in a surgical margin of the corresponding specimen.

Conclusion

Our data show that noninvasive fields surrounding HNSCC may consist of immortalized preneoplastic cell clones. Our preneoplastic cell line is a valuable tool to develop and test treatment strategies for precursor fields in patients with HNSCC. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Identification of novel target proteins in sebaceous gland carcinoma
Authors: Erovic Boban M. , Al Habeeb Ayman , Harris Luke , Goldstein David P. , Kim Dae , Ghazarian Danny , Irish Jonathan C.
Published: June 2012

Background

The aim of this study was to identify new target proteins in sebaceous gland carcinoma.

Methods

A tissue microarray containing 115 core biopsies was constructed and stained for proteins involved in carcinogenesis, angiogenesis, inflammation, and cell‐to‐cell contact. Two investigators independently determined protein expression of all antibodies.

Results

Vascular endothelial growth factor receptor 2 (VEGFR‐2), platelet‐derived growth factor receptor alpha and beta (PDGFR‐α/‐β), epidermal growth factor receptor (EGFR), cyclooxygenase 1 and 2 (Cox‐1/‐2), myeloid cell leukemia sequence 1 (Mcl‐1), matrix metalloproteinase 1 (MMP‐1), CD9, Bmi‐1, 14‐3‐3σ, glutathione S‐transferase pi (Gstπ), and members of the sonic hedgehog (SHH), AKT, and WNT pathways were significantly overexpressed in sebaceous gland carcinomas.

Conclusions

We have demonstrated for the first time that proteins related to angiogenesis, inflammation, and cell proliferation are overexpressed in sebaceous gland carcinomas. These proteins may hold promise as novel therapeutic targets for the treatment of sebaceous gland carcinoma. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Usefulness of cone‐beam CT for presurgical assessment of keratoma (cholesteatoma) of the maxillary sinus
Authors: Buric Nikola , Jovanovic Goran , Tijanic Milos
Published: June 2012

Background

Evaluating the presurgical usefulness of cone‐beam CT (CBCT) in the diagnosis and subsequent surgery of keratoma (cholesteatoma) of the maxillary sinus.

Methods

CBCT scans were obtained by using 3‐dimensional CT (3DCT) apparatus. The exposure factors had a field of view of 16 × 12 cm, 120 kVp, 7 mA, and an exposure time of 20 seconds. The acquired image data consisted of a 14‐bit sensor that delivers 16,384 shades of gray with a standard isotropic cubic voxel size of 0.3 mm.

Results

The CBCT scans clearly demonstrated a 22‐ × 16.82‐ × 17.62‐mm expansile lesion in the left maxillary sinus area, with thin cortical plates, and a focal perforation of the medial cortical plate at the level of the apices.

Conclusion

All CBCT visual data provide impressive, full 3D images of maxillary sinus keratoma, and help us to perform successful surgery. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
Lyase activity of glycogen synthase: Is an elimination/addition mechanism a possible reaction pathway for retaining glycosyltransferases?
Authors: Díaz Adelaida , Díaz‐Lobo Mireia , Grados Enrique , Guinovart Joan J. , Fita Ignacio , Ferrer Joan C.
Published: June 2012

Despite the biological relevance of glycosyltrasferases (GTs) and the many efforts devoted to this subject, the catalytic mechanism through which a subclass of this large family of enzymes, namely those that operate with net retention of the anomeric configuration, has not been fully established. Here, we show that in the absence of an acceptor, an archetypal retaining GT such as Pyrococcus abyssi glycogen synthase (PaGS) reacts with its glucosyl donor substrate, uridine 5'‐diphosphoglucose (UDP‐Glc), to produce the scission of the covalent bond between the terminal phosphate oxygen of UDP and the sugar ring. X‐ray diffraction analysis of the PaGS/UDP‐Glc complex shows no electronic density attributable to the UDP moiety, but establishes the presence in the active site of the enzyme of a glucose‐like derivative that lacks the exocyclic oxygen attached to the anomeric carbon. Chemical derivatization followed by gas chromatography/mass spectrometry of the isolated glucose‐like species allowed us to identify the molecule found in the catalytic site of PaGS as 1,5‐anhydro‐D‐arabino‐hex‐1‐enitol (AA) or its tautomeric form, 1,5‐anhydro‐D‐fructose. These findings are consistent with a stepwise SNi‐like mechanism as the modus operandi of retaining GTs, a mechanism that involves the discrete existence of an oxocarbenium intermediate. Even in the absence of a glucosyl acceptor, glycogen synthase (GS) promotes the formation of the cationic intermediate, which, by eliminating the proton of the adjacent C2 carbon atom, yields AA. Alternatively, these observations could be interpreted assuming that AA is a true intermediate in the reaction pathway of GS and that this enzyme operates through an elimination/addition mechanism. © 2012 IUBMB Life, 2012.
Modulation of temporomandibular joint nociception and inflammation in male rats after administering a physiological concentration of 17β‐oestradiol
Authors: Kramer P.R. , Bellinger L.L.
Published: June 2012

Background

Previous studies have shown 17β‐estradiol will reduce temporomandibular joint (TMJ) inflammation and hypersensitivity in female rats. Although male rats contain significant amounts of oestradiol, it was unknown whether a physiological concentration of 17β‐estradiol would attenuate male TMJ inflammation and nociception.

Methods

Intact and castrated rats were given a physiological concentration of oestradiol to examine first, if oestradiol will affect male TMJ nociception/inflammation and, second, if administration of oestradiol would act synergistically with endogenous male hormones to attenuate TMJ nociception. The hormonally treated rats were given TMJ injections of complete Freund's adjuvant (CFA) and then nociception was measured using a validated method in which a lengthening in meal duration is directly correlated to the intensity of deep TMJ nociception. Inflammation was assayed by quantitating pro‐inflammatory gene expression.

Results

Meal duration was significantly lengthened after TMJ CFA injection and this lengthening was significantly attenuated in the castrated but not intact males after administering a physiological concentration of oestradiol. A physiological concentration of 17β‐estradiol also significantly increased IL‐6 expression in the inflamed TMJ of castrated males while 17β‐estradiol did not alter IL‐1β, CXCL2 and CCL20 expression. Castration increased pro‐inflammatory mediators IL‐6, IL‐1β and CXCL2 suggesting male sex hormones were anti‐inflammatory. Calcitonin gene‐related peptide in the trigeminal ganglia was unchanged.

Conclusions

Similar to females, male rats with TMJ inflammation showed a reduced nociceptive response after treatment with a physiological concentration of oestradiol suggesting the effects of oestradiol treatment were not constrained by organizational processes in the males.
KEEPING MEANS AND ENDS IN VIEW—LINKING PRACTICAL JUDGEMENT, ETHICS AND EMERGENCE
Authors: Mowles Chris
Published: June 2012

In this article I argue that the means and ends of development are constitutive of each other. If means appear to have become separated from the espoused ends of international nongovernment organisations (INGOs), then it may be because other ends, the corporate aspirations of INGOs often expressed in grand strategies and plans, have come to dominate. However, in recognising that in development management particular methods that privilege the abstract and instrumental have come to dominate, this does not close off all possibility of critical reflection, discussion and negotiation, through the exercise of practical judgement or phronesis. Wholesale schemes for doing good, no matter how idealised and abstract, must be functionalised in particular contexts with particular people and can still be negotiated, affording the potential for the emergence of greater mutual recognition between those engaged in development. This negotiation and exploration of difference is often uncomfortable as each of the parties, and their power relationships, is made more visible to the other, but, this article argues, it is a prerequisite for continuously appraising our ethical engagement with others and for keeping means and ends in view. Copyright © 2012 John Wiley & Sons, Ltd.
ENGAGEMENT, LEARNING AND EMANCIPATORY DEVELOPMENT MANAGEMENT: A COMMENTARY
Authors: Johnson Hazel , Pinder Richard , Wilson Gordon
Published: June 2012

Complex and constantly emerging relationships between groups, organisations and movements aiming to promote and manage change bring into sharp focus the nature of means and ends and how they interact. Development managers are continually negotiating these relationships, where the tools (the means) and the espoused goals of development (the ends) are caught up in the process. We argue that although it is essential to recognise the role of power relations in development management, social difference and contestation experienced in the negotiation of changing relationships can create spaces and be important sources of engagement and learning for development managers and their organisations. A question is whether and how such learning can lead to more emancipatory means and ends of development management, rather than simply consolidating existing social relations. In this article, we provide a commentary on these issues through interviews with a small group of practitioners working mainly in non‐governmental organisations. Copyright © 2012 John Wiley & Sons, Ltd.
THE PEOPLE NEED TO MAKE THE TRAINS RUN ON TIME FOR EMPOWERMENT TO HAPPEN: MANAGERIALISM AND REVOLUTION IN NICARAGUA
Authors: Stookey Sarah
Published: June 2012

This article extends Gulrajani's proposal (2007) for a non‐managerialist alternative to the dichotomy posited by the radical and reformist critiques of development management. Drawing on extensive personal participation in development work during and after the Sandinista period, the author proposes that in Nicaragua a practice of development management emerged that defies the radical–reformist dichotomy. Unlike the alternative that Gulrajani proposed, it is argued that this practice had managerialist characteristics but that this reinforced rather than undermined progressive social change. The occurrence of this managerialism of the revolution, grounded in the Sandinista ethos of popular power and shaped by local history, conditions, and the extreme demands of national defence, suggests that development ends and managerialism are not necessarily antithetical. Copyright © 2012 John Wiley & Sons, Ltd.
Persistence of immunity to tick‐borne encephalitis after vaccination and natural infection
Authors: Baldovin Tatjana , Mel Rosanna , Bertoncello Chiara , Carpenè Graziella , Soppelsa Fabio , Giliberti Aurore , Baldo Vincenzo
Published: June 2012

Long‐term persistence of immunity was assessed in 66 patients who had contracted tick‐borne encephalitis (TBE) and in 126 subjects who had completed primary TBE immunization using a conventional three‐dose schedule from 3 to 8 years earlier. Immunity was tested in the subjects stratified by age as follows: ≤40 years (N = 37); 41–60 years (N = 100); and over 60 years (N = 55). Antibody levels decreased significantly with increasing age in the vaccinated cohort by comparison with the individuals who had previously contracted TBE. Consistently higher geometric mean antibody levels were found in the patients infected naturally. When the vaccinated subjects were compared, subjects ≤40 years old had significantly higher antibody levels than either of the older groups. Analyzing immunity to TBE over time revealed a remarkable (50%) decline in seroprotection rates in the vaccinated group at 50 months of follow‐up, while stable, high levels persisted in all subjects after natural TBE infection. In the vaccinees over 60 years old, the TBE antibody levels reached 60% at 60 months, and 20% at 70 months of follow‐up; in contrast, in the 41–60‐year‐old group, the antibody levels remained high for 70 months, and then fell rapidly. For people aged <60 years old, booster doses are recommended every 5 years after the fourth dose of vaccine, which should be administered 3 years after primary immunization. In subjects aged 60 years or older, booster doses should be given every 3 years. J. Med. Virol. 84: 1274–1278, 2012. © 2012 Wiley Periodicals, Inc.
Genetic characterization of seoul hantavirus originated from norway rats (Rattus norvegicus) captured in Belgium
Authors: Plyusnina Angelina , Heyman Paul , Baert Kristof , Stuyck Jan , Cochez Christel , Plyusnin Alexander
Published: June 2012

Hantaviruses (genus Hantavirus, family Bunyaviridae) cause hemorrhagic fever with renal syndrome (HFRS) in Eurasia and hantavirus (cardio)pulmonary syndrome (HCPS) in the Americas. So far, in Europe, four pathogenic hantaviruses have been found, often in co‐circulation: Puumala virus (PUUV), Dobrava virus (DOBV), Saaremaa virus (SAAV), and Seoul virus (SEOV). Of those, only PUUV was found in Belgium. Recently, in our search for hantaviruses in the Flanders region of Belgium we collected genetic and serological evidence for the presence of SEOV virus in local brown rats. In this article, the results of (phylo)genetic analysis of wild‐type SEOV strain from the Flanders are presented. The analysis based on the complete S segment sequence and also partial M‐ and L‐segment sequences revealed that the Belgian SEOV strain was related most closely to strains from France, Indonesia, Japan, Singapore, Cambodia (those associated with the species Rattus norvegicus) and Vietnam. Such a clustering was in perfect agreement with the results of direct sequence comparison and suggested the same evolutionary history for all three genome segments of the Belgian SEOV strain (i.e., no reassortment of genome segments). So far, SEOV has been found in two European countries, France and Belgium, and there is every reason to believe that the area of the virus distribution in Europe is not restricted to those countries. J. Med. Virol. 84: 1298–1303, 2012. © 2012 Wiley Periodicals, Inc.
In vitro replication phenotype of a novel (−1G) hepatitis B virus variant associated with HIV co‐infection
Authors: Cabuang Liza M. , Shaw Tim , Littlejohn Margaret , Colledge Danni , Sozzi Vitini , Soppe Sally , Warner Nadia , Thompson Alex , Preiss Scott , Lam Natasha , Walsh Renae , Lewin Sharon R. , Thio Chloe L. , Matthews Gail , Locarnini Stephen A. , Revill Peter A.
Published: June 2012

The −1G mutant HBV is more prevalent in individuals co‐infected with HIV/HBV than in individuals infected with HBV alone and in some cases is the dominant virus in circulation. This mutant is created by the deletion of a dGMP (−1G) from the guanine rich homopolymer sequence located at nts 2,085–2,090 (numbering from EcoRI site as position 1) in the HBV core gene. This deletion causes a frameshift generating a premature stop codon at 64Asn in the HBV core gene (codon 93 in the precore gene), that truncates the precore protein, precursor of the secreted hepatitis B “e” antigen (HBeAg), and the core protein which forms the viral nucleocapsid. However, the replication phenotype of the −1G mutant HBV is unknown. An in vitro cell culture model in which hepatoma cells were transiently transfected with infectious cDNAs was used to show that the −1G mutant HBV is incapable of autonomous replication and, as expected, replication was restored to wild‐type (wt) levels by supplying HBV core protein in trans. Although the −1G mutation had no deleterious effect on intracellular HBV‐DNA levels, high levels of −1G mutant HBV relative to wt HBV reduced virus secretion and HBeAg secretion relative to empty vector controls. Importantly, the −1G mutant HBV also caused intracellular retention of truncated precore protein in the endoplasmic reticulum (ER) and Golgi apparatus. Together, these effects may be contributing to the increased pathology observed in the setting of HIV/HBV co‐infection. J. Med. Virol. 84: 1166–1176, 2012. © 2012 Wiley Periodicals, Inc.
Epidemiology of respiratory virus infections among infants and young children admitted to hospital in Oman
Authors: Khamis F.A. , Al‐Kobaisi M.F. , Al‐Areimi W.S. , Al‐Kindi H. , Al‐Zakwani I.
Published: June 2012

The aim of this prospective study was to determine the epidemiology of respiratory viruses responsible for seasonal epidemics of influenza‐like illness in infants and young children in Oman. All children ≤5 years of age consecutively admitted to Sultan Qaboos University Hospital in Oman over a 1‐year period between December 2007 and December 2008 with acute respiratory infections were included. A multiplex polymerase chain reaction (PCR) for viral detection was performed on nasopharyngeal aspirates. Analyses were conducted using univariate statistical methods. Of the 259 infants and young children, at least one respiratory virus was detected in 130 samples (50%). The most prevalent viruses were respiratory syncytial virus (RSV; 43%; n = 56), adenovirus (15%; n = 20), and parainfluenza virus (PIV) (11%; n = 14). Dual or multiple viral infections were found in 23 cases (18%). The three most prominent symptoms of the cohort were fever (78%; n = 201), tachypnoea (77%; n = 200), and runny nose (61%; n = 158). The majority had bronchiolitis (39%; n = 101) while 37% (n = 96) had pneumonia. RSV was more likely to affect those that were young (4 months vs. 7.5 months; P = 0.002) and had tachypnoea (93% vs. 69%; P = 0.004), lower respiratory tract infections (91% vs. 80%; P = 0.039), and bronchiolitis (57% vs. 38%; P = 0.024). The study indicated that respiratory viruses are highly prevalent in children ≤5 years presenting with acute respiratory infections in Oman, of which RSV is the most prominent. J. Med. Virol. 84: 1323–1329, 2012. © 2012 Wiley Periodicals, Inc.
Surface modification counteracts adverse effects associated with immobilization after flexor tendon repair
Authors: Zhao Chunfeng , Sun Yu‐Long , Jay Gregory D. , Moran Steven L. , An Kai‐Nan , Amadio Peter C.
Published: June 2012

Although post‐rehabilitation is routinely performed following flexor tendon repair, in some clinical scenarios post‐rehabilitation must be delayed. We investigated modification of the tendon surface using carbodiimide derivatized hyaluronic acid and lubricin (cd‐HA‐Lub) to maintain gliding function following flexor tendon repair with postoperative immobilization in a in vivo canine model. Flexor digitorum profundus tendons from the 2nd and 5th digits of one forepaw of six dogs were transected and repaired. One tendon in each paw was treated with cd‐HA‐Lub; the other repaired tendon was not treated. Following tendon repair, a forearm cast was applied to fully immobilize the operated forelimb for 10 days, after which the animals were euthanized. Digit normalized work of flexion (nWOF) and tendon gliding resistance were assessed. The nWOF of the FDP tendons treated with cd‐HA‐Lub was significantly lower than the nWOF of the untreated tendons (p < 0.01). The gliding resistance of cd‐HA‐Lub treated tendons was also significantly lower than that of the untreated tendons (p < 0.05). Surface treatment with cd‐HA‐Lub following flexor tendon repair provides an opportunity to improve outcomes for patients in whom the post‐operative therapy must be delayed after flexor tendon repair. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1940–1944, 2012
Cloud‐point extraction combined with HPLC for determination of larotaxel in rat plasma: A pharmacokinetic study of liposome formulation
Authors: Ma Haiying , You Jian , Liu Yafei
Published: June 2012

A simple and efficient method based on cloud‐point extraction combined with high‐performance liquid chromatography was developed and validated for the determination of larotaxel in rat plasma. Nonionic surfactant Triton X‐114 was chosen as the extraction solvent. Variable parameters affecting the cloud‐point extraction efficiency, for example the nature and concentration of surfactant, NaOH concentration, incubation temperature, and time were evaluated and optimized. Chromatographic separation was accomplished on a Diamonsil C18 column (150 mm × 4.6 mm, 5 μm) using a mobile phase consisting of acetonitrile and 0.1% phosphoric acid with pH 4.0 (60:40, v/v). The calibration curve showed good linearity over the range of 0.05–10 μg/mL. Under the optimum conditions, the method was shown to be reproducible and reliable with intraday precision below 5.7%, interday precision below 7.2%, accuracy within ±3.5%, and mean extraction recovery of 91.8–94.2%. The validated method was successfully applied to the pharmacokinetic study of larotaxel in rat plasma after a single intravenous administration of larotaxel injection and larotaxel‐loaded liposome, respectively. The results indicated that the larotaxel‐loaded liposome led to significant differences in pharmacokinetic profile.
A single nucleotide polymorphism in microRNA‐146a is associated with the risk for nasopharyngeal carcinoma
Authors: Lung Raymond Wai‐Ming , Wang Xingyan , Tong Joanna Hung‐Man , Chau Shuk‐Ling , Lau Kin‐Mang , Cheng Shuk‐Hang , Woo John Kong‐Sang , Woo Jean , Leung Ping‐Chung , Ng Margaret Heung‐Ling , Tang Nelson Leung‐Sang , To Ka‐Fai
Published: June 2012

A common GC polymorphism within miRNA‐146a precursor region (rs2910164) has been associated with the risk of various cancers despite the underlying mechanism is unclear. In the current study, we aimed to examine the role of rs2910164 in the pathogenesis and predisposition to nasopharyngeal carcinoma (NPC). The GC polymorphism in 233 NPC patients, 173 matched controls and 3613 healthy elderly subjects in our locality were first determined using melting temperature (Tm)‐shift allele‐specific genotyping method. Results in our case–control study indicated that CC genotype was associated with the risk effect of NPC (adjusted odds ratio of GC + GG vs. CC, 0.49; 95% confidence interval, 0.35–0.69; P < 0.0001). Using real‐time polymerase chain reaction (PCR) assay, we subsequently revealed that expressions of both miR‐146a and its passenger strand (miR‐146a*C or miR‐146a*G) were increased in NPC samples (P < 0.001), albeit expression of miR‐146a was not linked to the genotype. Furthermore, miR‐146a*C in NPC was significantly increased in CC genotype (CC vs. GC, P = 0.038). Finally, we demonstrated by co‐immunoprecipitation and luciferase reporter assays that all three miR‐146a precursor‐derived mature miRNAs interacted with Argonaute2 (Ago2) protein complex and could function as gene silencers. Taken together, our results showed that the variant C in rs2910164 was associated with the predisposition of NPC in Chinese population. This polymorphism may influence the risk of NPC by producing active mature miR‐146a*C that regulate distinct set of target genes. These findings may enrich our understanding of how miRNA single nucleotide polymorphism affect NPC pathogenesis, and may have potential implications to improve NPC treatment in the future. © 2012 Wiley Periodicals, Inc.
Homotopy analysis method to obtain numerical solutions of the Painlevé equations
Authors: Hesameddini Esmail , Latifizadeh Habibolla
Published: June 2012

In this paper, the homotopy analysis method (HAM) is presented to obtain the numerical solutions for the two kinds of the Painlevé equations with a number of initial conditions. Then, a numerical evaluation and comparison with the results obtained via the HAM are included. It illustrates the validity and the great potential of the HAM in solving Painlevé equations. Although the HAM contains the auxiliary parameter, the convergence region of the series solution can be controlled in a simple way. Copyright © 2012 John Wiley & Sons, Ltd.
Periodic substrate structure suppresses spurious response in coupled line filters
Authors: Saeidi Chiya , van der Weide Daniel
Published: June 2012

Periodic perturbation of the dielectric medium following Bragg's law and equalizing mode velocities together suppress the first spurious response in coupled‐line filters. The design parameters are calculated using the classical coupled‐line filter design. Fabricating a Chebyshev filter; for the bisected unit cell, spurious response suppression of 35 dB is achieved. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2175–2178, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26999
Fast analysis of arbitrary beam through planar multilayer structures
Authors: Liang Bin , Bai Ming , Ou Naiming , Jin Ming , Miao Jungang
Published: June 2012

In this article, a fast and accurate method is presented for analyzing the interaction between arbitrary oriented finite beams over planar multilayer structures.The method is based on Transfer Matrix algorithm and optical fast‐Fourier‐transform based angular spectrum method. Full vectorial near‐fields of electromagnetic beam refracted and reflected by the multilayer can be calculated within several seconds. A numerical simulation in FEKO and an experiment are respectively implemented, and good agreement compared with the hybrid method is obtained. The method can be used in the design process of the multilayer with big amount of parameter adjustment, and then full‐wave simulation can be adopted to get exact results. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2185–2190, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27014
Multibias neural modeling of fin field‐effect transistor admittance parameters
Authors: Marinković Zlatica , Crupi Giovanni , Schreurs Dominique M. M.‐P. , Caddemi Alina , Marković Vera
Published: June 2012

The goal of this study is to develop an artificial neural network (ANN) approach to model the fin field‐effect transistor (FinFET) small‐signal admittance parameters. The model is determined for the whole device as well as for the actual transistor, which is obtained after de‐embedding the effects of the probe pads, transmission lines, and substrate. The extracted model is validated in a wide range of operating bias conditions up to 50 GHz. In comparison to the earlier developed ANN‐based model of the FinFET scattering parameters, although the same accuracy is achieved, the proposed technique exhibits the main advantage of a reduced model complexity. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2082–2088, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27020
Maximum efficiency radiofrequency shimming: Theory and initial application for hip imaging at 7 tesla
Authors: Deniz Cem Murat , Brown Ryan , Lattanzi Riccardo , Alon Leeor , Sodickson Daniel K. , Zhu Yudong
Published: June 2012

Radiofrequency shimming with multiple channel excitation has been proposed to increase the transverse magnetic field uniformity and reduce specific absorption rate at high magnetic field strengths (≥7 T) where high‐frequency effects can make traditional single channel volume coils unsuitable for transmission. In the case of deep anatomic regions and power‐demanding pulse sequences, optimization of transmit efficiency may be a more critical requirement than homogeneity per se. This work introduces a novel method to maximize transmit efficiency using multiple channel excitation and radiofrequency shimming. Shimming weights are calculated in order to obtain the lowest possible net radiofrequency power deposition into the subject for a given transverse magnetic field strength. The method was demonstrated in imaging studies of articular cartilage of the hip joint at 7 T. We show that the new radiofrequency shimming method can enable reduction in power deposition while maintaining an average flip angle or adiabatic condition in the hip cartilage. Building upon the improved shimming, we further show that the signal‐to‐noise ratio in hip cartilage at 7 T can be substantially greater than that at 3 T, illustrating the potential benefits of high field hip imaging. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Preparation and properties of peroxide dynamically vulcanized polypropylene/ethylene‐propylene‐diene monomer/zinc dimethacrylate thermoplastic olefin
Authors: Chen Yu‐kun , Xu Chuan‐hui , Wang Yan‐peng
Published: June 2012

Attempts were made to prepare the polypropylene (PP) /ethylene‐propylene‐diene monomer (EPDM) blends with zinc dimethacrylate (ZDMA) via peroxide dynamic vulcanization. PP was melt‐mixed with EPDM and ZDMA at different compositions (PP/EPDM/ZDMA, i.e., 70/30/0, 70/30/3, 70/30/6, and 70/30/9, w/w/w) using an internal mixer at 50 rpm rotor speed. The addition of ZDMA improved the rheological properties of the resulting materials in the melt state. The morphological studies revealed that the addition of ZDMA led to an improvement of size reduction and distribution uniformity for crosslinked EPDM phase. ZDMA showed a positive effect on the mechanical properties of the PP/EPDM/ZDMA composites, particularly on the toughness and extensibility. With the incorporation of ZDMA, the izod impact strength and the elongation of PP/EPDM/ZDMA composites increased from 41 kJ/m2 to 72 kJ/m2 and 110% to 495%, respectively. The crystallization behaviors analysis indicated that the addition of ZDMA promoted the nucleation process of PP but the crystallinity of the PP phase was decreased at the meantime. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
Molecular dynamics analyses of the dissociation process of ADP from Hsp90
Authors: Kawaguchi Kazutomo , Takagi Hiroyuki , Iwayama Masashi , Nishimura Megumi , Miyakawa Takeshi , Saito Hiroaki , Takasu Masako , Nagao Hidemi
Published: June 2012

Hsp90 (90 kDa heat shock protein) is a molecular chaperon involved in protein folding and regulating the stability and activation state of many client proteins under stress and normal conditions. Hsp90 is an attractive target for the therapeutics against cancer and virus infectious diseases. Hsp90 undergoes large conformational changes during its functional cycle driven by ATP binding and hydrolysis to ADP at the N‐terminal domain. ATP‐binding and ADP‐dissociation play key roles for the functions of Hsp90. All‐atom molecular dynamics simulations of the N‐terminal domain of human Hsp90 in complex with ADP are carried out to elucidate the dissociation process of ADP at atomic resolution. The MD simulations with the binding‐distance constraint are performed. Our results show that ADP is dissociated from the binding pocket of Hsp90 with Mg2+, and that ADP has two possible conformation and two possible pathways in the dissociation process. © 2012 Wiley Periodicals, Inc.
Theoretical calculation of the zero‐temperature isotherm and phase stability of silver up to 2 Gbar using the linear combinations of gaussian type orbitals method
Authors: Boettger Jonathan C.
Published: June 2012

A systematic procedure has been developed for generating the static lattice zero temperature isotherm of a monatomic crystalline solid to arbitrarily high compressions using the linear combinations of Gaussian type orbitals‐fitting function electronic structure method. This procedure has been used to calculate the static‐lattice equation of state and phase stability of silver (Ag) up to 2 Gbar. The resulting isotherm is compared with previous density functional theory (DFT) calculations and experimental data at low pressures and with results from Thomas–Fermi–Dirac calculations at high pressures. The stabilities of three crystal structures (face centered cubic, fcc; body centered cubic, bcc; and hexagonal close packed, hcp) were determined from energy differences calculated up to 2 Gbar. The effects of relativity and DFT model selection were tested by repeating each calculation with and without relativistic corrections using two DFT models; the local density (LDA) and generalized gradient (GGA) approximations. The phase sequence for Ag is predicted to be fcc → hcp → fcc → hcp → bcc, although the second appearance of the hcp phase is questionable due to convergence issues. © 2012 Wiley Periodicals, Inc.
Ionization potential and ion yield of CsM clusters sputtered from Si
Authors: Kudriavtsev Yu. , Asomoza R. , Mansurova M. , Perez L. A.
Published: June 2012

We calculated the ionization potentials for 34 CsM molecules (where M is the element of the periodic table) by using SIESTA code, on the basis of the density functional theory. The calculated ionization potentials of CsM molecules were found essentially less than the ionization potentials of related atoms. Experimental SIMS relative sensitivity factors were found for the CsM+ cluster ions by using implanted standards. Exponential dependence between the relative sensitivity factors of CsM+ cluster ions and their ionization potentials was obtained. This lets us suggest that there is a direct emission of the CsM molecules during the cesium ion beam sputtering process; ionization of the CsM molecules occurs at the emitted surface because of the same mechanism as for sputtered atoms. Copyright © 2012 John Wiley & Sons, Ltd.
Systems biology approaches to toll‐like receptor signaling
Authors: Vandenbon Alexis , Teraguchi Shunsuke , Akira Shizuo , Takeda Kiyoshi , Standley Daron M.
Published: June 2012

Toll‐like receptor (TLR) signaling pathways constitute an evolutionarily conserved host defense system that protects against a broad range of infectious agents. Modeling of TLR signaling has been carried out at several levels. Structural models of TLRs and their adaptors, which utilize a small number of structural domains to recognize a diverse range of pathogens, provide a starting point for understanding how pathogens are recognized and signaling events initiated. Various experimental and computational techniques have been used to construct models of downstream signal transduction networks from the measurements of gene expression and chromatin structure under resting and perturbed conditions along with predicted regulatory sequence motifs. Although a complete and accurate mathematical model of all TLR signaling pathways has yet to be derived, many important modules have been identified and investigated, enhancing our understanding of innate immune responses. Extensions of these models based on emerging experimental techniques are discussed. WIREs Syst Biol Med 2012 doi: 10.1002/wsbm.1178

This article is categorized under:

Models of Systems Properties and Processes > Cellular Models

Biological Mechanisms > Cell Signaling

Analytical and Computational Methods > Computational Methods

Models of Systems Properties and Processes > Mechanistic Models
Tolerance of High‐Intensity Focused Ultrasound Ablation in Patients with Hepatocellular Carcinoma
Authors: Cheung Tan To , Chu Ferdinand S. K. , Jenkins Caroline R. , Tsang Dickson S. F. , Chok Kenneth S. H. , Chan Albert C. Y. , Yau Thomas C. C. , Chan See Ching , Poon Ronnie T. P. , Lo Chung Mau , Fan Sheung Tat
Published: June 2012

Background

High‐intensity focused ultrasound (HIFU) ablation is a relatively new, noninvasive way of ablation for treating hepatocellular carcinoma (HCC). Emerging evidence has shown that it is effective for the treatment of HCC, even in patients with poor liver function. There is currently no data on the safety limit of HIFU ablation in patients with cirrhosis. However, this information is vital for the selection of appropriate patients for the procedure. We analyzed HCC patients who had undergone HIFU ablation and determined the lower limit of liver function and other patient factors with which HCC patients can tolerate this treatment modality.

Methods

Preoperative variables of 100 patients who underwent HIFU ablation for HCC were analyzed to identify the risk factors in HIFU intolerance in terms of stress‐induced complications. Factors that may contribute to postablation complications were compared.

Results

Thirteen (13 %) patients developed a total of 18 complications. Morbidity was mainly due to skin and subcutaneous tissue injuries (n = 9). Five patients had first‐degree skin burn, one had second‐degree skin burn, and three had third‐degree skin burn. Four complications were grade 3a in the Clavien classification and 14 were below this grade. Univariate analysis showed that age (p = 0.022) was the only independent factor in HIFU intolerance.

Conclusions

HIFU ablation is generally well tolerated in HCC patients with cirrhosis. It is safe for Child‐Pugh A and B patients and selected Child‐Pugh C patients. With this new modality, HCC patients who were deemed unsalvageable by other surgical means in the past because of simultaneous Child‐Pugh B or C disease now have a new hope.
Strength of sliding knots in multifilament resorbable suture materials
Authors: van Leeuwen Nourah , Trimbos J. Baptist
Published: June 2012

Experimental laboratory study was made to test the knot integrity of identical, non-identical and parallel sliding knots, with three and five throws, made with synthetic resorbable multifilament suture materials. The knots were made with Novosyn (polyglactin 612), Safil (polyglycolic acid), Vicryl (polyglactin 612) and Vicryl plus (polyglactin 910 + triclosan), all with suture size: 3-0 USP. Per material 10 knots for every kind of knot were tested in a tensiometer, resulting in a total of 240 tests. Sliding knots with three throws were compared with the five throw sliding knots, and a comparison of the loop-holding capacities (LHC) of the different suture materials was made. Differences in suture material, knot type, and number of throws in the knot had a remarkable effect on knot performance. Adding two extra throws to a three throw non-identical or parallel sliding knot resulted in significantly more reliable knots (P < 0.05). In identical sliding knots, this effect was not seen, but these knots showed low LHCs, indicating poor knot reliability. Compared to the other suture materials, Safil showed significantly lower LHCs. Most of the mean LHCs of the various knots with Vicryl, Vicryl Plus or Novosyn were not statistically different from each other. Identical sliding knots appeared to be very unreliable, especially when made with three throws. Non-identical and parallel slipknots with five throws demonstrated superior knot integrity compared with the same knot types with three throws. Safil had inferior knot properties as compared to the other materials, but Vicryl, Vicryl Plus and Novosyn behaved virtually the same. The type of knot and the use of different suture materials have important influence on the integrity of the knot. A high knot reliability is nowadays all the more important because of the frequent use of resorbable suture materials. The suture gradually loses strength during the resorption process, so that an extra margin of safety neutralizes the effect of this process.
Regional Anesthesia for Children Undergoing Orthopedic Ambulatory Surgeries in the United States, 1996–2006
Authors: Kuo Cassie , Edwards Alison , Mazumdar Madhu , Memtsoudis Stavros G.
Published: June 2012

Background

Our objective was to evaluate national trends in regional anesthetic techniques among children undergoing ambulatory orthopedic procedures.

Purpose and Questions

We aimed to determine whether an increase in regional anesthetics was primarily driven by an increase in the number of peripheral nerve blocks performed rather than an increase in neuraxial techniques. We further aimed to determine whether the proportion of peripheral nerve blocks performed in conjunction with general anesthesia has increased over time.

Patients and Methods

Our study sample included any pediatric patient (i.e., <18 years old) who underwent an orthopedic ambulatory procedure in 1996 and 2006. We obtained data on ambulatory surgical procedures by accessing the Centers for Disease Control and Prevention's National Survey of Ambulatory Surgery. Patient demographics (age, gender), procedure information, and anesthesia-related variables were analyzed for each year.

Results

The proportion of peripheral nerve blocks performed for ambulatory surgery more than doubled from 1996 (4.4 %) to 2006 (8.1 %). A significantly larger proportion of orthopedic procedures were being performed with a combination of peripheral nerve blocks and general anesthesia (1.2 % in 1996 and 43 % 2006). The use of neuraxial anesthesia for lower extremity surgeries decreased over the 10-year period (1.1 and 0.4 % in 1996 and 2006, respectively).

Conclusions

There was a significant increase in the use of peripheral nerve blocks for children undergoing ambulatory orthopedic procedures in the USA, while neuraxial techniques became less common over the 10-year period. The peripheral nerve blocks were frequently performed in conjunction with general anesthesia.