bluuebunny/crossref_metadata_2025_split huggingface dataset:
Broad‐range bacterial polymerase chain reaction in the microbiologic diagnosis of complicated pneumonia
Authors: Gollomp Kandace , Rankin Shelley C. , White Caitlin , Mattei Peter , Harris Mary C. , Kilpatrick Laurie E. , Sheffler‐Collins Seth , McGowan Karin L. , Shah Samir S. 
Published: October 2011

AbstractBACKGROUND:A bacterial cause is not frequently identified in children with pneumonia complicated by parapneumonic effusion (ie, complicated pneumonia).OBJECTIVES:To determine the frequency of positive blood and pleural fluid cultures in children with complicated pneumonia and to determine whether broad‐range 16S rRNA polymerase chain reaction (PCR) improves identification of a microbiologic cause.METHODS:This prospective cohort study included children 1–18 years of age hospitalized with complicated pneumonia.RESULTS:Pleural fluid drainage was performed in 64 (51.6%) of 124 children with complicated pneumonia. A microbiologic cause was identified in 11 of 64 patients (17.2%; 95% confidence interval [CI]: 8.9%–28.7%). Bacteria were isolated from pleural fluid culture in 6 of 64 patients (9.4 %; 95% CI: 3.5%–19.3%) undergoing pleural drainage; the causative bacteria were Staphylococcus aureus (n = 5) and Streptococcus pneumoniae (n = 1). Blood culture identified a bacterial cause in 3 of 44 cases (6.8%; 95% CI: 1.4%–18.7%) undergoing pleural fluid drainage; S. pneumoniae (n = 1), Haemophilus influenzae (n = 1), and S. aureus (n = 1) were isolated. Only 3 of the 19 pleural fluid samples (15.8%; 95% CI: 3.4%–39.6%) analyzed with 16S rRNA PCR were positive. S. pneumoniae was the only organism detected in all three samples; two of these three had negative pleural fluid cultures and absence of bacteria on Gram stain. S. aureus was isolated from pleural fluid culture in one patient with a negative 16S rRNA PCR test.CONCLUSIONS:Causative bacteria were infrequently identified in children with complicated pneumonia. Broad‐range 16S rRNA PCR only modestly improved the microbiologic yield over conventional culture methods. Journal of Hospital Medicine 2011. © 2011 Society of Hospital Medicine
Experimental assessment of toxic phytochemicals in Jatropha curcas: oil, cake, bio‐diesel and glycerol
Authors: Pradhan Subhalaxmi , Naik S N , Khan M Ashhar I , Sahoo PK 
Published: October 2011

AbstractBACKGROUND: Jatropha curcas seed is a rich source of oil; however, it can not be utilised for nutritional purposes due to presence of toxic and anti‐nutritive compounds. The main objective of the present study was to quantify the toxic phytochemicals present in Indian J. curcas (oil, cake, bio‐diesel and glycerol).RESULTS: The amount of phorbol esters is greater in solvent extracted oil (2.8 g kg−1) than in expeller oil (2.1 g kg−1). Liquid chromatography‐mass spectroscopy analysis of the purified compound from an active extract of oil confirmed the presence of phorbol esters. Similarly, the phorbol esters content is greater in solvent extracted cake (1.1 g kg−1) than in cake after being expelled (0.8 g kg−1). The phytate and trypsin inhibitory activity of the cake was found to be 98 g kg−1 and 8347 TIU g−1 of cake, respectively. Identification of curcin was achieved by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis and the concentration of curcin was 0.95 g L−1 of crude concentrate obtained from cake.CONCLUSION: Higher amounts of phorbol esters are present in oil than cake but bio‐diesel and glycerol are free of phorbol esters. The other anti‐nutritional components such as trypsin inhibitors, phytates and curcin are present in cake, so the cake should be detoxified before being used for animal feed. Copyright © 2011 Society of Chemical Industry
Immunoaffinity purification of α‐momorcharin from bitter melon seeds (Momordica charantia)
Authors: Yao Xingchuan , Li Juan , Deng Nianhua , Wang Shurui , Meng Yanfa , Shen Fubing 
Published: October 2011

Abstractα‐Momorcharin (α‐MMC), a type I ribosome‐inactivating protein (RIP), has shown therapeutic potential such as anti‐tumor and anti‐viral agent. Traditional process of α‐MMC purification from bitter melon seeds was time consuming and low efficient. To take this challenge, we made an affinity matrix by coupling the monoclonal antibody (McAb) with Sepharose 4B. Using this attractive strategy, 196 mg of α‐MMC was obtained from 100 g of bitter melon seeds as the starting material. The yield of the protein was 2.7%. The homogeneity and properties of the protein were assessed by SDS‐PAGE, acidic PAGE, RP‐HPLC and N‐terminal sequence as well as Western blot. Purified α‐MMC showed remarkable inhibition to the melanoma cell line JAR and EMT‐62058. In addition, it also displayed obvious inhibition on hepatitis B virus (HBV). This work provided a simple, rapid and efficient approach for α‐MMC purification from Momordica charantia.
Determination of oleanolic and ursolic acid in Chinese herbs using HPLC and γ‐CD as mobile phase modifier
Authors: Wang Changhe , Liu Haijing , Zhang Binghua , Guo Huanying 
Published: October 2011

AbstractTo separate and determine oleanolic acid and ursolic acid, a rapid and accurate HPLC using γ‐CD as the mobile phase additive was developed. The effect of CD nature and concentration, and the acidity of the mobile phase on the chromatographic behavior of two bioactive triterpenes were systematically studied. Two bioactive triterpenes were completely separated (R = 3.11) on a Kromasil® C18 column (150×4.6 mm id, 5 μm) with the mobile phase consisting of acetonitrile/0.1% phosphoric acid with 2 mM γ‐CD as the mobile phase modifier (60:40, v/v). The flow rate was set at 1.0 mL/min and the eluent was detected at 210 nm for two bioactive triterpenes. The linearity of the method was excellent (r=0.9999) over the studied range of 6–300 μg/mL for oleanolic acid, and 12–600 μg/mL for ursolic acid. The LOD and LOQ were 1.5 and 5.0, 1.0 and 3.0 μg/mL for oleanolic acid and ursolic acid, respectively. The optimized method was successfully applied to separate and determine two bioactive triterpenes in five Chinese herbs. It is concluded that this method could be used for rapid and accurate qualitative and quantitative analysis of the two bioactive triterpenes in Chinese herbs.
Chromatographic retention and thermodynamics of adsorption of dipeptides on a chiral crown ether stationary phase
Authors: Asnin Leonid , Sharma Kavita , Park Se Won 
Published: October 2011

AbstractThe enantioselective adsorption of several dipeptides on the crown ether‐based stationary phase ChiroSil RCA(+) was studied by means of the linear chromatography method. The retention of analytes was measured with acidified water–methanol mobile phases with varied concentration of methanol (from 60 to 90%, v/v) at different temperatures. Thermodynamic characteristics of adsorption were determined and analyzed applying extrathermodynamic relationships. A considerable difference in adsorption mechanisms of dipeptides with a chiral and achiral N‐terminal fragment was proved. An explanation to this fact was proposed assuming that the enantiorecognition of the dipeptides of the first type occurred through the interaction of side groups of the N‐terminus with the chiral cavity formed by the crown ether ring. The enantiorecognition of the dipeptides of the second type occurs through the interaction of the C‐terminal residue with the side groups of the crown ether moiety. The study also demonstrates how extrathermodynamic concepts can be used for obtaining additional information about retention mechanisms from a limited amount of chromatographic data.
Polyinosine‐polycytidylic acid enhances cellular adherence of Streptococcus pneumoniae
Authors: Kawabata Masaki , Kurono Yuichi 
Published: October 2011

AbstractObjectives/Hypothesis:Viral upper respiratory tract infections (URIs) are often followed by secondary bacterial infections. To better understand this phenomenon, we examined the impact of the viral agent polyinosine‐polycytidylic acid [Poly (I:C)] on the adherence of Streptococcus pneumoniae (Spn) to pharyngeal epithelial cells.Study Design:In vitro model of cultured human pharyngeal epithelial cells.Methods:Detroit 562 cells, a human pharyngeal carcinoma cell line, were pretreated with Poly (I:C). Poly (I:C)–induced expression of platelet‐activating factor receptor (PAF‐R) was assayed using real‐time polymerase chain reaction, flow cytometry, and immunofluorescence microscopy. Bacterial adhesion to these epithelial cells was assessed using immunofluorescence microscopy and colony formation assays.Results:Pretreatment with Poly (I:C) increased mRNA and protein expression of PAF‐R in Detroit 562 cells and enhanced the adherence of Spn to these epithelial cells.Conclusions:RNA viral infection can enhance PAF‐R expression in epithelial cells and increase the adherence of Spn. These findings might explain in part the mechanisms that underlie the increase in bacterial infection following URIs.
Role of serotonergic 1A receptor dysfunction in depression associated with Parkinson's disease
Authors: Ballanger Benedicte , Klinger Helene , Eche Julien , Lerond Jérôme , Vallet Anne‐Evelyne , Le Bars Didier , Tremblay Leon , Sgambato‐Faure Véronique , Broussolle Emmanuel , Thobois Stéphane 
Published: October 2011

AbstractDepression is frequent in Parkinson's disease, but its pathophysiology remains unclear. Two recent studies have investigated the role of serotonergic system at the presynaptic level. The objective of the present study was to use positron emission tomography and [18F]MPPF to investigate the role of postsynaptic serotonergic system dysfunction in the pathophysiology of depression in Parkinson's disease. Four parkinsonian patients with depression and 8 parkinsonian patients without depression were enrolled. Each patient underwent a scan using [18F]MPPF, a selective serotonin 1A receptor antagonist. Voxel‐by‐voxel statistical comparison of [18F]MPPF uptake of the 2 groups of parkinsonian patients and with 7 matched normal subjects was made using statistical parametric mapping (P uncorrected < .001). Compared with nondepressed parkinsonian patients, depressed patients exhibited reduced tracer uptake in the left hippocampus, the right insula, the left superior temporal cortex, and the orbitofrontal cortex. Compared with controls, nondepressed parkinsonian patients presented reduced [18F]MPPF uptake bilaterally in the inferior frontal cortex as well as in the right ventral striatum and insula. Compared with controls, [18F]MPPF uptake was decreased in depressed parkinsonian patients in the left dorsal anterior cingulate and orbitofrontal cortices, in the right hippocampic region, and in the temporal cortex. The present imaging study suggests that abnormalities in serotonin 1A receptor neurotransmission in the limbic system may be involved in the neural mechanisms underlying depression in patients with Parkinson's disease. © 2011 Movement Disorder Society
Mammalian septins: dynamic heteromers with roles in cellular morphogenesis and compartmentalization
Authors: Hall Peter A , Russell SE Hilary 
Published: October 2011

AbstractThe septins are a family of GTP‐binding proteins, evolutionarily conserved from yeast through to mammals, with roles in multiple core cellular functions. Here we provide an overview of our current knowledge of septin structure and function and focus mainly on mammalian septins, but gain much insight by drawing on knowledge of septins in other organisms. We describe their genomic and transcriptional complexity: a complexity manifest also in the diversity of scaffold structures that septins can form. Septin complexes can act to localize interacting proteins at specific intracellular locales and can also define membrane compartments by defining diffusion barriers. By such activities, septins can contribute to the definition of spatial asymmetry and cell polarity and we suggest a potential role in stem cell biology. Finally, we review the evidence that septins contribute to various disease states and argue that it is a breakdown in the tight regulation of their expression (particularly of individual isoforms), and also their inherent ability to oligomerize, which is pathogenic. Study of the perturbation of septin complex formation in disease will provide valuable insights into septin biology and will be a fertile ground for study. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Mitochondrial DNA and disease
Authors: Greaves Laura C , Reeve Amy K , Taylor Robert W , Turnbull Doug M 
Published: October 2011

AbstractMitochondrial DNA (mtDNA) defects are a relatively common cause of inherited disease and have been implicated in both ageing and cancer. MtDNA encodes essential subunits of the mitochondrial respiratory chain and defects result in impaired oxidative phosphorylation (OXPHOS). Similar OXPHOS defects have been shown to be present in a number of neurodegenerative conditions, including Parkinson's disease, as well as in normal ageing human tissues. Additionally, a number of tumours have been shown to contain mtDNA mutations and an altered metabolic phenotype. In this review we outline the unique characteristics of mitochondrial genetics before detailing important pathological features of mtDNA diseases, focusing on adult neurological disease as well as the role of mtDNA mutations in neurodegenerative diseases, ageing and cancer. Copyright © 2011 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Mechanical, thermal, and rheological behavior of ethylene methyl acrylate‐MWNT nanocomposites
Authors: Basuli Utpal , Chaki Tapan Kumar , Chattopadhyay Santanu 
Published: October 2011

AbstractMechanical, thermal, and rheological properties of ethylene methyl acrylate (EMA) composites reinforced with multiwalled carbon nanotubes (MWNTs) have been reported here. Morphological analyses revealed that MWNTs are more uniformly dispersed in EMA upto 3.5 wt% MWNTs loading. Uniform dispersion of MWNTs in EMA matrix leads to decreased crystallinity and increased crystallite size. These are reflected in the mechanical and thermal properties of the composites. The storage moduli of the composites significantly increase by the incorporation of MWNTs, particularly at higher temperatures. The nanocomposites register a slightly higher viscosity than that of neat EMA depending on the contents of MWNTs. Storage modulus (in dynamic shear) increases especially at higher frequency levels due to increased polymer–filler interactions. Dynamic and steady shear rheological properties register a good correlation in regard to the viscous versus elastic response of the nanocomposites. The morphology correlates well with the dynamic rheological characteristics of these nanocomposites. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Studies of the moisture‐sensitive shape memory effect of pyridine‐containing polyurethanes
Authors: Chen Shaojun , Hu Jinlian , Chen Shiguo 
Published: October 2011

AbstractShape memory polymers have been much researched in recent years. In the work reported, moisture‐sensitive shape memory effects (SMEs) of novel pyridine‐containing shape memory polyurethanes (Py‐SMPUs) were investigated systematically. The results show that the strain recovery start immersion time (ts), strain recovery immersion time (tr) and final strain recovery immersion time (te) are prolonged with a decrease of relative humidity as well as a decrease of temperature. The final strain recovery decreases with a decrease of relative humidity as well as an increase of temperature. The key component affecting the moisture‐sensitive SME is the N,N‐bis(2‐hydroxyethyl)isonicotinamide (BINA) unit. The lower limit of BINA content for Py‐SMPUs to exhibit a good moisture‐sensitive SME is 30 wt%. The addition of diphenylmethane diisocyanate (MDI) and 1,4‐butanediol (BDO) enhances the moisture‐sensitive shape recovery. The final shape recovery decreases with a decrease of BINA content or an increase of MDI–BDO content. In addition, ts, tr and te become shorter in the Py‐SMPUs with higher BINA content or with lower MDI‐BDO content. Copyright © 2011 Society of Chemical Industry
The dual role of fragments in fragment‐assembly methods for de novo protein structure prediction
Authors: Handl Julia , Knowles Joshua , Vernon Robert , Baker David , Lovell Simon C. 
Published: October 2011

AbstractIn fragment‐assembly techniques for protein structure prediction, models of protein structure are assembled from fragments of known protein structures. This process is typically guided by a knowledge‐based energy function and uses a heuristic optimization method. The fragments play two important roles in this process: they define the set of structural parameters available, and they also assume the role of the main variation operators that are used by the optimiser. Previous analysis has typically focused on the first of these roles. In particular, the relationship between local amino acid sequence and local protein structure has been studied by a range of authors. The correlation between the two has been shown to vary with the window length considered, and the results of these analyses have informed directly the choice of fragment length in state‐of‐the‐art prediction techniques. Here, we focus on the second role of fragments and aim to determine the effect of fragment length from an optimization perspective. We use theoretical analyses to reveal how the size and structure of the search space changes as a function of insertion length. Furthermore, empirical analyses are used to explore additional ways in which the size of the fragment insertion influences the search both in a simulation model and for the fragment‐assembly technique, Rosetta. Proteins 2012. © 2011 Wiley Periodicals, Inc.
Bihelix: Towards de novo structure prediction of an ensemble of G‐protein coupled receptor conformations
Authors: Abrol Ravinder , Bray Jenelle K. , Goddard William A. 
Published: October 2011

AbstractG‐Protein Coupled Receptors (GPCRs) play a critical role in cellular signal transduction pathways and are prominent therapeutic targets. Recently there has been major progress in obtaining experimental structures for a few GPCRs. Each GPCR, however, exhibits multiple conformations that play a role in their function and we have been developing methods aimed at predicting structures for all these conformations. Analysis of available structures shows that these conformations differ in relative helix tilts and rotations. The essential issue is, determining how to orient each of the seven helices about its axis since this determines how it interacts with the other six helices. Considering all possible helix rotations to ensure that no important packings are overlooked, and using rotation angle increments of 30° about the helical axis would still lead to 127 or 35 million possible conformations each with optimal residue positions. We show in this paper how to accomplish this. The fundamental idea is to optimize the interactions between each pair of contacting helices while ignoring the other 5 and then to estimate the energies of all 35 million combinations using these pair‐wise interactions. This BiHelix approach dramatically reduces the effort to examine the complete set of conformations and correctly identifies the crystal packing for the experimental structures plus other near‐native packings we believe may play an important role in activation. This approach also enables a detailed structural analysis of functionally distinct conformations using helix‐helix interaction energy landscapes and should be useful for other helical transmembrane proteins as well. Proteins 2012. © 2011 Wiley Periodicals, Inc.
Structural and binding studies of the C‐terminal domains of yeast TFIIF subunits Tfg1 and Tfg2
Authors: Kilpatrick Adina M. , Koharudin Leonardus M.I. , Calero Guillermo A. , Gronenborn Angela M. 
Published: October 2011

AbstractThe general transcription factor TFIIF plays essential roles at several steps during eukaryotic transcription. While several studies have offered insights into the structure/function relationship in human TFIIF, much less is known about the yeast system. Here, we describe the first NMR structural and binding studies of the C‐terminal domains (CTDs) of Tfg1 and Tfg2 subunits of Saccharomyces cerevisiae TFIIF. We used the program CS‐ROSETTA to determine the three‐dimensional folds of these domains in solution, and performed binding studies with DNA and protein targets. CS‐ROSETTA models indicate that the Tfg1 and Tfg2 C‐terminal domains have winged‐helix architectures, similar to the human homologs. We showed that both Tfg1 and Tfg2 CTDs interact with double‐stranded DNA oligonucleotides, and mapped the DNA binding interfaces using solution NMR. Tfg1‐CTD, but not Tfg2‐CTD, also binds to yeast FCP1, an RNA polymerase II‐specific phosphatase, and we delineated the interaction surface with the CTD of FCP1. Our results provide insights into the structural basis of yeast TFIIF function and the differential roles of Tfg1 and Tfg2 subunits during transcription. Proteins 2012. © 2011 Wiley Periodicals, Inc.
Autonomous transportation and deployment with aerial robots for search and rescue missions
Authors: Bernard Markus , Kondak Konstantin , Maza Ivan , Ollero Anibal 
Published: October 2011

AbstractIt is generally accepted that systems composed of multiple aerial robots with autonomous cooperation capabilities can assist responders in many search and rescue (SAR) scenarios. In most of the previous research work, the aerial robots are mainly considered as platforms for environmental sensing and have not been used to assist victims. In this paper, outdoor field experiments of transportation and accurate deployment of loads with single/multiple autonomous aerial vehicles are presented. This is a novel feature that opens the possibility to use aerial robots to assist victims during rescue phase operations. Accuracy in the deployment location is a critical issue in SAR scenarios in which injured people may have very limited mobility. The presented system is composed of up to three small‐size helicopters and features cooperative sensing, using several different sensor types. The system supports several forms of cooperative actuation as well, ranging from the cooperative deployment of small sensors/objects to the coupled transportation of slung loads. The complete system is described, outlining the hardware and software framework used, as well as the approaches for modeling and control used. Additionally, the results of several flight field experiments are presented, including a description of the worldwide first successful autonomous load transportation experiment, using three coupled small‐size helicopters (conducted in December 2007). During these experiments strong, steady winds and wind gusts were present. Various solutions and lessons learned from the design and operation of the system are also provided. © 2011 Wiley Periodicals, Inc.
A new method for efficient three‐dimensional reconstruction of outdoor environments using mobile robots
Authors: Fentanes Jaime A. Pulido , Alonso Raul Feliz , Zalama Eduardo , García‐Bermejo Jaime Gómez 
Published: October 2011

AbstractIn this paper, a method for robotic exploration oriented to the automatic three‐dimensional (3D) reconstruction of outdoor scenes is presented. The proposed algorithm focuses on optimizing the exploration process by maximizing map quality, while reducing the number of scans required to create a good‐quality 3D model of the environment. This is done by using expected information gain, expected model quality, and trajectory cost estimation as criteria for view planning. The method has been tested with an all‐terrain mobile robot, which is also described in the paper. This robot is equipped with a SICK LMS 111 laser scanner attached to a spinning turret, which performs quick and complete all‐around scans. Different experiments of autonomous 3D exploration show the suitable performance of the proposed exploration algorithm. © 2011 Wiley Periodicals, Inc.