bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mitsunobu Reaction: A Versatile Tool for PEG End Functionalization
Authors: d'Arcy Richard , Tirelli Nicola 
Published: August 2015

The Mitsunobu reaction can be efficiently used for the transformation of poly(ethylene glycol) (PEG) terminal OH group(s) into a variety of functions. In comparison to more classical approaches of PEG functionalization, the main advantage of the Mitsunobu reaction attains to the fact that in one step, with no detrimental effect on PEG integrity (e.g., chain cleavage). Here, its quantitative conversion is demonstrated into derivatives that, either directly or after deprotection, are amenable to (bio)conjugation reactions: azides (Huisgen cycloaddition), aldehydes, primary amines (Schiff base formation and reduction), thiols, and N‐oxymaleimide (Michael‐type addition). Therefore this reaction is proposed as a general tool for the preparation of functionalities for the purpose of PEGylation, and more generally for (bio)conjugation purposes.
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Advances in the treatment of cognitive impairment inParkinson's disease
Authors: Goldman Jennifer G. , Weintraub Daniel 
Published: August 2015

ABSTRACTCognitive impairment in Parkinson's disease (PD) is a frequent complication, with significant interindividual variability in clinical symptoms, severity, timing, and neural substrates. Recent studies have focused not only on understanding PD dementia, but also mild cognitive impairment in PD, which may represent a prodromal stage for dementia. In recent years, there have been important advances regarding clinical characterizations, definitions, associated biomarkers, and risk factors for both mild cognitive impairment in PD and PD dementia. However, there is a paucity of effective therapies for cognitive impairment in PD, whether for mild symptoms or for moderate to severe dementia. At present, only rivastigmine is U.S. Food and Drug Administration approved for PD dementia, an indication received nearly a decade ago. Given the frequency of PD cognitive impairment and its substantial impact on both patients and families, the lack of available and effective treatments represents a striking gap in the field, especially when compared to the large number of available therapies for PD motor symptoms and complications. Improved symptomatic therapies, as well as potential disease‐modifying agents, for PD cognitive impairment are needed. Most therapeutic trials for PD dementia and mild cognitive impairment in PD have focused on drugs developed for and tested in Alzheimer's disease, such as cholinesterase inhibitors and the N‐methyl‐D‐aspartate receptor antagonist, memantine, though recent and ongoing trials examine the effects of pharmacological agents affecting other neurotransmitters, as well as nonpharmacological therapies, including mental and physical exercise and neurostimulation. This review summarizes the design and outcomes of trials for PD cognitive impairment published since 2013 and highlights future therapeutic research opportunities and challenges. © 2015 International Parkinson and Movement Disorder Society
The gga‐let‐7 family post‐transcriptionally regulates TGFBR1 and LIN28B during the differentiation process in early chick development
Authors: Lee Sang In , Jeon Mi‐hyang , Kim Jeom Sun , Jeon Ik‐Soo , Byun Sung June 
Published: August 2015

SUMMARYEarly chick embryogenesis is governed by a complex mechanism involving transcriptional and post‐transcriptional regulation, although how post‐transcriptional processes influence the balance between pluripotency and differentiation during early chick development have not been previously investigated. Here, we characterized the microRNA (miRNA) signature associated with differentiation in the chick embryo, and found that as expression of the gga‐let‐7 family increases through early development, expression of their direct targets, TGFBR1 and LIN28B, decreases; indeed, gga‐let‐7a‐5p and gga‐let‐7b miRNAs directly bind to TGFBR1 and LIN28B transcripts. Our data further indicate that TGFBR1 and LIN28B maintain pluripotency by regulating POUV, NANOG, and CRIPTO. Therefore, gga‐let‐7 miRNAs act as post‐transcriptional regulators of differentiation in blastodermal cells by repressing the expression of the TGFBR1 and LIN28B, which intrinsically controls blastodermal cell differentiation in early chick development. Mol. Reprod. Dev. 82: 967–975, 2015. © 2015 Wiley Periodicals, Inc.
Correcting heat‐induced chemical shift distortions in proton resonance frequency‐shift thermometry
Authors: Gaur Pooja , Partanen Ari , Werner Beat , Ghanouni Pejman , Bitton Rachelle , Butts Pauly Kim , Grissom William A 
Published: August 2015

PurposeTo reconstruct proton resonance frequency‐shift temperature maps free of chemical shift distortions.Theory and MethodsTissue heating created by thermal therapies such as focused ultrasound surgery results in a change in proton resonance frequency that causes geometric distortions in the image and calculated temperature maps, in the same manner as other chemical shift and off‐resonance distortions if left uncorrected. We propose an online‐compatible algorithm to correct these distortions in 2DFT and echo‐planar imaging acquisitions, which is based on a k‐space signal model that accounts for proton resonance frequency change‐induced phase shifts both up to and during the readout. The method was evaluated with simulations, gel phantoms, and in vivo temperature maps from brain, soft tissue tumor, and uterine fibroid focused ultrasound surgery treatments.ResultsWithout chemical shift correction, peak temperature and thermal dose measurements were spatially offset by approximately 1 mm in vivo. Spatial shifts increased as readout bandwidth decreased, as shown by up to 4‐fold greater temperature hot spot asymmetry in uncorrected temperature maps. In most cases, the computation times to correct maps at peak heat were less than 10 ms, without parallelization.ConclusionHeat‐induced proton resonance frequency changes create chemical shift distortions in temperature maps resulting from MR‐guided focused ultrasound surgery ablations, but the distortions can be corrected using an online‐compatible algorithm. Magn Reson Med 76:172–182, 2016. © 2015 Wiley Periodicals, Inc.
A randomized trial of diagnostic ultrasound to improve outcomes in focal neuropathies
Authors: Cartwright Michael S. , Griffin Leah P. , Dowlen Hugh , Bargoil Jessica M. , Caress James B. , Li Zhongyu J. , Defranzo Anthony J. , Wiesler Ethan R. , Tuohy Christopher J. , Balakrishnan Nikhil , Molnar Joseph A. , Baute Vanessa , Koman L. Andrew , Poehling Gary G. , Walker Francis O. 
Published: August 2015

ABSTRACTIntroduction: Neuromuscular ultrasound is valid, reliable, and accurate, but it is not known whether combining it with electrodiagnostic studies leads to better outcomes in individuals with focal neuropathies. Methods: One hundred twenty individuals with focal neuropathy, based on history, examination, and electrodiagnosis, were enrolled in this study. All patients underwent neuromuscular ultrasound and were randomized to either have their ultrasound results sent to the referring physician or not have them sent. Outcomes were assessed at 6 months by evaluators blinded to group assignment. Results: The Overall Disability Sum Score and 7 of 8 domains of the Medical Outcomes Study 36‐item Short‐Form Health Survey (SF‐36) showed more improvement in the “report sent” group, although only the general health perception domain was significant (P = 0.005). Conclusions: Most 6‐month outcomes did not reach statistical significance between the 2 groups. However, the “report sent” group had trends toward better outcomes, with significance being reached in the general health perception domain of the SF‐36. Muscle Nerve 52: 746–753, 2015
Atherosclerosis as a predictor of delayed recovery from lower urinary tract dysfunction after robot‐assisted laparoscopic radical prostatectomy
Authors: Yabe Michihiro , Haga Nobuhiro , Ogawa Soichiro , Kataoka Masao , Akaihata Hidenori , Sato Yuichi , Hata Junya , Ishibashi Kei , Kojima Yoshiyuki 
Published: August 2015

AimsThe aim of the present study was to investigate whether atherosclerosis could be associated with lower urinary tract dysfunction in the early postoperative period after robot‐assisted laparoscopic radical prostatectomy (RARP).MethodsEighty consecutive patients undergoing RARP were investigated. The severity of atherosclerosis was evaluated by the cardio‐ankle vascular index (CAVI) before RARP. Patients were divided into two groups, the atherosclerotic group (CAVI ≥9.0) and the control group (CAVI <9.0). International Prostate Symptom Score (IPSS), quality of life (QOL) index, uroflowmetry, post‐void residual urine volume (PVR), frequency–volume charts, and the 1‐hr pad test were compared between the two groups. Assessments were performed before RARP, and then at 1, 3, and 6 months after RARP.ResultsPreoperative subjective and objective parameters were not significantly different between the two groups. The voiding symptom score of the IPSS and the QOL index was significantly higher in the atherosclerotic group at 3 months after RARP (P = 0.035, P = 0.001, respectively). The maximum flow rate was consistently lower in the atherosclerotic group, reaching a significant difference at 6 months after RARP (P = 0.027). IPSS total and storage symptom scores, PVR, frequency, and urine loss were not significantly different between the groups after RARP.ConclusionsAtherosclerosis delayed the improvement of both voiding symptoms and voiding function after RARP, leading to aggravation of QOL in the early postoperative period. Atherosclerosis may be a predictor of slower recovery from transient lower urinary tract dysfunction immediately after RARP. Neurourol. Urodynam. 35:920–925, 2016. © 2015 Wiley Periodicals, Inc.
The prevalence of fecal incontinence and associated risk factors in older adults participating in the SABE study
Authors: Tamanini José Tadeu Nunes , de Jesus Felipe Alves , Castro Rodrigo Aquino , Ferreira Sartori Marair Gracio , Castello Girão Manoel João Batista , dos Santos Jair Lício Ferreita , de Oliveira Duarte Yeda Aparecida , Lebrão Maria Lúcia 
Published: August 2015

AimsTo assess the prevalence of fecal incontinence (FI) and associated factors in older adults.MethodsThe prevalence and factors associated with FI in older adults were studied by means the SABE study (Health, Well‐being, and Aging). A group of 1,345 subjects were interviewed during the third wave of the SABE study performed in Sao Paulo, in 2010. The study included 64.3% females; the mean age of the participants was 70.4 years. The dependent variable was the positive answer for the question “In the last 12 months, have you ever lost control of bowel movements or stools?”. Descriptive analysis and hierarchical logistic regression were performed. The independent variables were as follows: (a) demographics: gender, age and (b) clinical characteristics: self‐reported chronic diseases, presence of cognitive and/or functional decline, depression and urinary incontinence symptoms, and nutritional status.ResultsThe overall prevalence of FI was 11,7%, being 8.3% and 13.2% for males and females respectively. Among male subjects, the presence of malnutrition was associated with FI and thus presented a high relative risk index for its occurrence. Among female subjects, age group 70–74 years and some self‐reported diseases or conditions such as mild depression, heart disease, urinary incontinence, and polypharmacy were associated with FI. For the first time in literature, polypharmacy appeared as an associated factor for FI for female older adults.ConclusionsThe prevalence of FI in older adults was 11.7% and was mainly associated with advanced age and presence of heart disease, symptoms of depression, polypharmacy and urinary incontinence and malnutrition. Neurourol. Urodynam. 35:959–964, 2016. © 2015 Wiley Periodicals, Inc.
Balancing the energy equation for healthy kidneys
Authors: Mount Peter F , Power David A 
Published: August 2015

AbstractThe high‐energy requirement of the kidney and the importance of energy metabolism in renal physiology has been appreciated for decades, but only recently has there emerged a strong link between impaired renal energy metabolism and chronic kidney disease (CKD). The mechanisms underlying the association between changes in energy metabolism and progression of CKD, however, remain poorly understood. A new study from Qiu and colleagues reported in the Journal of Pathology has advanced this understanding by showing that, after renal injury, the energy sensor AMPK inhibits epithelial–mesenchymal transition and inflammation, processes important in the pathogenesis of CKD. Furthermore, this study identifies an interaction between AMPK and CK2β as an important mechanism in the anti‐fibrotic effect. CK2β has previously been shown to interact with STK11 (also known as LKB1) to regulate cellular polarity. These findings are consistent with the known roles of the LKB1–AMPK pathway in sustaining cellular energy homeostasis and epithelial cell polarity, and add to growing evidence linking the suppression of energy metabolism to CKD. They emphasize the importance of energy metabolism in general and the LKB1–AMPK axis in particular as key investigational and therapeutic targets in the battle against CKD. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Sulfonated dendrimer‐ and hyperbranched polyglycerol‐PBIOO® blend membranes for fuel cells
Authors: Martín‐Zarco Manuela , Titvinidze Giorgi , García‐Martínez Joaquín C. , Rodríguez‐López Julián 
Published: August 2015

ABSTRACTA new sulfonated dendrimer with an arylene ether sulfone backbone has been synthesized, fully characterized, and blended with PBIOO® to prepare acid‐base proton‐conducting membranes under different conditions and with different composition ratios. Water‐soluble sulfonated hyperbranched polyglycerols of different molecular weights were also used as the acidic components. Membrane properties such as ion‐exchange capacity, water uptake, thermal stability, proton conductivity, and morphology have been studied and discussed. The nature of the acidic component and the morphology of the membranes had a marked influence on the final properties. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 69–80
Synthesis and photovoltaic properties of 2,6‐bis(2‐thienyl) benzobisazole and 4,8‐bis(thienyl)‐benzo[1,2‐B:4,5‐B′]dithiophene copolymers
Authors: Bhuwalka Achala , Ewan Monique D. , Elshobaki Moneim , Mike Jared F. , Tlach Brian , Chaudhary Sumit , Jeffries‐EL Malika 
Published: August 2015

ABSTRACTIn an effort to design efficient low‐cost polymers for use in organic photovoltaic cells the easily prepared donor–acceptor–donor triad of a either cis‐benzobisoxazole, trans‐benzobisoxazole or trans‐benzobisthiazole flanked by two thiophene rings was combined with the electron‐rich 4,8‐bis(5‐(2‐ethylhexyl)‐thien‐2‐yl)‐benzo[1,2‐b:4,5‐b′]dithiophene. The electrochemical, optical, morphological, charge transport, and photovoltaic properties of the resulting terpolymers were investigated. Although the polymers differed in the arrangement and/or nature of the chalcogens, they all had similar highest occupied molecular orbital energy levels (−5.2 to −5.3 eV) and optical band gaps (2.1–2.2 eV). However, the lowest unoccupied molecular orbital energy levels ranged from −3.1 to −3.5 eV. When the polymers were used as electron donors in bulk heterojunction photovoltaic devices with PC71BM ([6,6]‐phenyl C71‐butyric acid methyl ester) as the acceptor, the trans‐benzobisoxazole polymer had the best performance with a power conversion efficiency of 2.8%. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 316–324
Combustion of Aluminum Particles near the Burning Surface in AP/AN Composite Propellants
Authors: Doi Rieko , Kuwahara Takuo 
Published: August 2015

AbstractAluminum (Al) particles are commonly used in ammonium perchlorate (AP) composite propellants of solid rockets for increasing performance. When propellants including Al particles burn, Al particles easily agglomerate on the burning surface of the propellant. The diameters of agglomerated Al particles are greater than those of mixed particles. The combustion efficiency of the propellant decreases with increasing burning time of the agglomerated Al particles. Therefore, it is important to observe how the agglomerated Al particles burn on the burning surface of AP composite propellant. A lot of researchers have studied Al agglomerate characteristics. Previous studies clarified the relation between the agglomerated Al particle diameter and luminous flame diameter around Al particles near the burning surface. The shapes of luminous flames around agglomerated Al particles are spherical or elliptical. This study evaluates the shapes of the luminous flame around agglomerated Al particles at a constant diameter or a different diameter. When the proportion of the luminous flame diameter (Df) to the diameter of agglomerated Al particles (D0) is 1.54–1.71 at a constant D0, the luminous flames are almost perfectly spherical. Otherwise, the luminous flames are elliptical at a constant D0. Furthermore, when Df/D0 is close to the mean value, the luminous flame is more spherical than elliptical at different D0. The evaporation rate and the burning rate of Al vapor are inversely proportional to D0. The oxidation gas temperatures were changed and the activation energy of Al vapor was obtained as 39.2 kJ mol−1.
Structure of HIV‐1 reverse transcriptase bound to a novel 38‐mer hairpin template‐primer DNA aptamer
Authors: Miller Matthew T. , Tuske Steve , Das Kalyan , DeStefano Jeffrey J. , Arnold Eddy 
Published: August 2015

AbstractThe development of a modified DNA aptamer that binds HIV‐1 reverse transcriptase (RT) with ultra‐high affinity has enabled the X‐ray structure determination of an HIV‐1 RT‐DNA complex to 2.3 Å resolution without the need for an antibody Fab fragment or RT‐DNA cross‐linking. The 38‐mer hairpin‐DNA aptamer has a 15 base‐pair duplex, a three‐deoxythymidine hairpin loop, and a five‐nucleotide 5′‐overhang. The aptamer binds RT in a template‐primer configuration with the 3′‐end positioned at the polymerase active site and has 2′‐O‐methyl modifications at the second and fourth duplex template nucleotides that interact with the p66 fingers and palm subdomains. This structure represents the highest resolution RT‐nucleic acid structure to date. The RT‐aptamer complex is catalytically active and can serve as a platform for studying fundamental RT mechanisms and for development of anti‐HIV inhibitors through fragment screening and other approaches. Additionally, the structure allows for a detailed look at a unique aptamer design and provides the molecular basis for its remarkably high affinity for RT.
Dynamics and thermodynamic properties of CXCL7 chemokine
Authors: Herring Charles A. , Singer Christopher M. , Ermakova Elena A. , Khairutdinov Bulat I. , Zuev Yuriy F. , Jacobs Donald J. , Nesmelova Irina V. 
Published: August 2015

ABSTRACTChemokines form a family of signaling proteins mainly responsible for directing the traffic of leukocytes, where their biological activity can be modulated by their oligomerization state. We characterize the dynamics and thermodynamic stability of monomer and homodimer structures of CXCL7, one of the most abundant platelet chemokines, using experimental methods that include circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopy, and computational methods that include the anisotropic network model (ANM), molecular dynamics (MD) simulations and the distance constraint model (DCM). A consistent picture emerges for the effects of dimerization and Cys5‐Cys31 and Cys7‐Cys47 disulfide bonds formation. The presence of disulfide bonds is not critical for maintaining structural stability in the monomer or dimer, but the monomer is destabilized more than the dimer upon removal of disulfide bonds. Disulfide bonds play a key role in shaping the characteristics of native state dynamics. The combined analysis shows that upon dimerization flexibly correlated motions are induced between the 30s and 50s loop within each monomer and across the dimer interface. Interestingly, the greatest gain in flexibility upon dimerization occurs when both disulfide bonds are present, and the homodimer is least stable relative to its two monomers. These results suggest that the highly conserved disulfide bonds in chemokines facilitate a structural mechanism that is tuned to optimally distinguish functional characteristics between monomer and dimer. Proteins 2015; 83:1987–2007. © 2015 Wiley Periodicals, Inc.
Detection of the F129L mutation in the cytochrome b gene in Phakopsora pachyrhizi
Authors: Klosowski Ana C , May De Mio Louise L , Miessner Simone , Rodrigues Ronaldo , Stammler Gerd 
Published: August 2015

AbstractBACKGROUNDAsian soybean rust, caused by Phakopsora pachyrhizi, is mostly controlled by demethylation inhibitor (DMI) and quinone outside inhibitor (QoI) fungicides. Mutations in the cytochrome b (CYTB) gene can lead to pathogen resistance to QoIs. The occurrence of the mutations in codons 129, 137 and 143 in the CYTB gene was investigated, and a pyrosequencing assay was developed for rapid and quantitative detection of the F129L mutation.RESULTSMolecular analysis of the CYTB gene showed the presence of the F129L mutation in field samples and monouredinial isolates, while other mutations (G143A and G137R) were not found. The pyrosequencing was an effective method for quantitative detection of the F129L mutation, and many of the P. pachyrhizi samples showed high frequency of F129L.CONCLUSIONThis is the first report of the occurrence of the F129L mutation in P. pachyrhizi. The practical relevance of this mutation for field efficacy of QoIs needs further investigation. © 2015 Society of Chemical Industry
Steroidal glycoalkaloids: chemical defence of edible African nightshades against the tomato red spider mite, Tetranychus evansi (Acari: Tetranychidae)
Authors: Jared Juma J , Murungi Lucy K , Wesonga John , Torto Baldwyn 
Published: August 2015

AbstractBACKGROUNDTetranychus evansi is an invasive pest of solanaceous crops in Africa, and in the field it differentially attacks edible African nightshades. The chemical basis for the differential attack on these plant species is largely unknown. Using bioassays and chemical analysis, we investigated the differential bioactivity of leaf extracts of three edible African nightshade species, Solanum sarrachoides, S. scabrum and S. villosum, on adult T. evansi females.RESULTSOnly the bioactivity of the leaf extract of S. sarrachoides (LC50 7.44 mg mL−1) and that of its most polar fraction (LC50 5.44 mg mL−1) paralleled that of the positive control, neem oil (LC50 1.89 mg mL−1), across all doses tested. Liquid chromatography–quadruple time of flight–mass spectrometry identified a mixture of steroidal glycoalkaloids (SGAs), including α‐solasonine, α‐solamargine and derivatives of tomatine and demissine, which were neither detected in the crude extract nor in any of the fractions obtained from S. scabrum and S. villosum.CONCLUSIONOur results suggest that the presence of SGAs may play a key role in the differential defence of edible African nightshades against attack by T. evansi. These findings may add to the plethora of environmentally friendly tools from natural plant products for management of T. evansi. © 2015 Society of Chemical Industry