bluuebunny/crossref_metadata_2025 huggingface dataset:
Unraveling the link between neuropathy target esterase NTE/SWS, lysosomal storage diseases, inflammation, abnormal fatty acid metabolism, and leaky brain barrier
Authors: Tsap Mariana I , Yatsenko Andriy S , Hegermann Jan , Beckmann Bibiana , Tsikas Dimitrios , Shcherbata Halyna R
Published: April 2024

Mutations in Drosophila Swiss cheese (SWS) gene or its vertebrate orthologue neuropathy target esterase (NTE) lead to progressive neuronal degeneration in flies and humans. Despite its enzymatic function as a phospholipase is well established, the molecular mechanism responsible for maintaining nervous system integrity remains unclear. In this study, we found that NTE/SWS is present in surface glia that forms the blood-brain barrier (BBB) and that NTE/SWS is important to maintain its structure and permeability. Importantly, BBB glia-specific expression of Drosophila NTE/SWS or human NTE in the sws mutant background fully rescues surface glial organization and partially restores BBB integrity, suggesting a conserved function of NTE/SWS. Interestingly, sws mutant glia showed abnormal organization of plasma membrane domains and tight junction rafts accompanied by the accumulation of lipid droplets, lysosomes, and multilamellar bodies. Since the observed cellular phenotypes closely resemble the characteristics described in a group of metabolic disorders known as lysosomal storage diseases (LSDs), our data established a novel connection between NTE/SWS and these conditions. We found that mutants with defective BBB exhibit elevated levels of fatty acids, which are precursors of eicosanoids and are involved in the inflammatory response. Also, as a consequence of a permeable BBB, several innate immunity factors are upregulated in an age-dependent manner, while BBB glia-specific expression of NTE/SWS normalizes inflammatory response. Treatment with anti-inflammatory agents prevents the abnormal architecture of the BBB, suggesting that inflammation contributes to the maintenance of a healthy brain barrier. Considering the link between a malfunctioning BBB and various neurodegenerative diseases, gaining a deeper understanding of the molecular mechanisms causing inflammation due to a defective BBB could help to promote the use of anti-inflammatory therapies for age-related neurodegeneration.
The role of mitophagy in the development of chronic kidney disease
Authors: Yang Kexin , Li Ting , Geng Yingpu , Zou Xiangyu , Peng Fujun , Gao Wei
Published: April 2024

Chronic kidney disease (CKD) represents a significant global health concern, with renal fibrosis emerging as a prevalent and ultimate manifestation of this condition. The absence of targeted therapies presents an ongoing and substantial challenge. Accumulating evidence suggests that the integrity and functionality of mitochondria within renal tubular epithelial cells (RTECs) often become compromised during CKD development, playing a pivotal role in the progression of renal fibrosis. Mitophagy, a specific form of autophagy, assumes responsibility for eliminating damaged mitochondria to uphold mitochondrial equilibrium. Dysregulated mitophagy not only correlates with disrupted mitochondrial dynamics but also contributes to the advancement of renal fibrosis in CKD. While numerous studies have examined mitochondrial metabolism, ROS (reactive oxygen species) production, inflammation, and apoptosis in kidney diseases, the precise pathogenic mechanisms underlying mitophagy in CKD remain elusive. The exact mechanisms through which modulating mitophagy mitigates renal fibrosis, as well as its influence on CKD progression and prognosis, have not undergone systematic investigation. The role of mitophagy in AKI has been relatively clear, but the role of mitophagy in CKD is still rare. This article presents a comprehensive review of the current state of research on regulating mitophagy as a potential treatment for CKD. The objective is to provide fresh perspectives, viable strategies, and practical insights into CKD therapy, thereby contributing to the enhancement of human living conditions and patient well-being.
MAPEO DINÁMICO DEL COMERCIO CALLEJERO EN SANTIAGO CENTRO
Authors: Valenzuela Nicolás , Ponce Javiera , Aguirre José , Iturrieta Danitza
Published: April 2024

Se presentan los resultados preliminares del levantamiento de datos georreferenciados de “coleros” y comercio callejero puntual en la comuna de Santiago, correspondientes a los primeros cinco trimestres de un total de ocho que serán registrados al terminar la investigación.
Identification of the Downy Mildew Resistant Sources in Sunflower
Authors: Dudhe M. Y. , Waghmare S. V. , Ramteke R. P. , Jadhav M. V. , Sakthivel K. , Dhuppe M. V. , Pole S. P. , Ghodke M. K. , Misal A. M. , Rajguru A. B.
Published: April 2024

Four different evaluation trials were conducted in the field between 2017 and 2020, with varied numbers of genotypes, to evaluate the performance of sunflower genotypes for agromorphological features and resistance to Sunflower Downy Mildew (SDM) at Latur, Maharashtra, India. A validation experiment was carried out in 2021–2022, using artificial screening in National Diseased Plot Screening Facility at Latur, to screen a small number of accessions that had previously shown resistance to SDM during 2017-2020. The released variety "Morden," also susceptible check showed at least 60% of the SDM incidence for four years. This suggests that Plasmopara halstedii spores could be present in the experimental soils, which increases the variety's susceptibility to SDM disease. Out of the tree genotypes that were reported to be resistant in field screening viz., GMU-481 (GP1 909 genotype), Ec-198078, and RHA 1-1 (selection) only two GMU-481 (GP1 909) and Ec-198078 were verified to be resistant under artificial screening in 2021–2022 and can be designated as sources of resistance for SDM disease. These two genotypes with resistance to SDM could be used in future breeding attempts and as potential gene donors for SDM.
Trauma-Related Deaths in the Accident and Emergency Department of a Nigerian Teaching Hospital
Authors: Tamunokuro Diamond , Amadi Christian Emeka
Published: April 2024

Background: Trauma is a significant contributor to morbidity, disabilities, loss of man hours and mortality in both the developed and developing world with 90% of global trauma deaths occurring in low and middle income countries. The extent of motor vehicular use, degree of adherence to use of safety gadgets, strength of enforcement of industrial safety regulations, level of civil unrest as well as other socio-demographic indices predict the contribution of various etiologic factors. Deaths from the trauma may perhaps have far more psychologic and physical impact on families that from acute/chronic medical cases
Method: A retrospective study of the admission records and in-patient records of all trauma related deaths in the accident and emergency unit of the University of Port Harcourt Teaching Hospital from 1st January 2018 to 31st December 2022 was done. Relevant information was extracted and analyzed. Data obtained was analyzed descriptively.  Results were presented in tables and                    charts where necessary.  Means and standard deviations were used to represent certain            variables.
Results: Total emergencies (medical and surgical) seen within the study period were 42,443, total injuries seen were 10,787 giving a crude injury prevalence rate of 25.4%. There were a total of 766 deaths among injured patients giving a crude mortality rate of 7.1%. Road traffic accidents (RTAs) (46.3%) and Firearm injuries (23.5%) were the most common injury mechanisms seen. Traumatic brain injuries are by far the leading cause of trauma-related deaths in the ER (82.5%) with most deaths (96.1%) occurring within the first 72hours of Admission.
Conclusion: Trauma-related deaths occur in 7.1% of all injuries presenting at the study sight. The most common mechanism is RTA while the most affected victim is the young adult male. Traumatic brain injury accounts for more deaths than all others combined with most of the deaths occurring within the first 72hours of presentation. All efforts at reducing these injuries should be encouraged.
STRATEGY FOR TEACHERS TO SUPPORT SELF-REGULATION FOR STUDENT LEARNING PROCESS IN POST-PANDEMIC LEARNING
Authors: Udju Lini Oltiovini , Setia Yulia , Lin Ivy Mary
Published: April 2024

Christian education aims to form students who have Christ-like qualities. This effort is a mission that Christian education wants to achieve. To develop these qualities, students need good self-regulation skills in learning. Self-regulation is the ability of students to direct their thoughts, feelings, and behavior to achieve learning goals. Students who have good self-regulation will achieve success in learning. However, since post-pandemic learning, students have had challenges adapting from online learning to face-to-face learning. This affects student self-regulation in learning. Therefore, Christian teachers, as shepherds, have a responsibility to help students experience increased self-regulation. In this study, researchers wanted to examine the strategies used by a teacher to support student self-regulation in the post-pandemic learning context. This study uses descriptive qualitative research methods with observation and interviews as data collection techniques. The data were then analyzed using data reduction, presentation, and conclusion. After examining more deeply, the researchers found that the teacher implemented several essential strategies in the context of post-pandemic learning and were proven to support students in experiencing increased self-regulation abilities in the learning process.
Imagens de eunucos africanos
Authors: Correa Silvio Marcus de Souza
Published: April 2024

As imagens dos eunucos africanos têm origens diversas. Da tradição pictórica europeia, o “orientalismo” foi uma delas. Uma iconografia orientalista sobre os eunucos africanos aparece ainda tanto na imprensa periódica ilustrada quando na literatura de viagem. Uma teratologia médica tratou, igualmente, dos eunucos. Enquanto registro visual de “tipos” humanos, a fotografia de eunucos africanos fez parte do inventário teratológico de um mundo que desaparecia na perspectiva dos impérios coloniais. Com base num corpus iconográfico com imagens de diferentes suportes materiais, discute-se a paradoxal “subalternidade” dos eunucos africanos e busca-se perceber a voz inaudível dos mesmos na historiografia. Por fim, mapeia-se um trajeto sinuoso da mutilação genital masculina à emasculação simbólica dos africanos no imaginário colonial.
Entre escravizados e camaradas, um senhor
Authors: Araújo Sabrina , Marin Jérri Roberto
Published: April 2024

O objetivo deste trabalho é analisar o processo-crime da comarca de Santa Cruz de Corumbá, na província de Mato Grosso, tramitado entre os anos de 1878 e 1886. O documento trata dos assassinatos do proprietário de terras Firmiano Firmino Ferreira Candido e do capataz João Pedro cometidos pelos seus escravizados e camaradas, em razão dos excessivos castigos corporais e do atraso no pagamento de salários. Posteriormente, houve uma tentativa de fuga para a Bolívia, mas os assassinos foram presos e julgados, exceto o camarada João Ignácio, que conseguiu fugir. A partir desse episódio, pretende-se abordar as motivações dos crimes e contribuir para o entendimento das complexas relações de trabalho entre as diferentes categorias sociais, bem como discorrer sobre as características do povoamento e ocupação desse cenário rural e fronteiriço.
manual de como fazer Sociologia a partir do continente asiático
Authors: Rocha Marianne da Silva
Published: April 2024

Resenha de:ALATAS, Syed Farid; SINHA, Vineeta. Teoria sociológica além do cânone. São Paulo: Editora Funilaria, 2023. 336 p.
Quantum Yield Measurement of Fluorescent Zeolite Nanopigments
Authors: Nicolet Olivier , Huber Stefan , Lovey Caroline , Chappellet Sabrina , Perrenoud Juliette , Pauchard Marc , Ferrini Rolando , Zuppiroli Libero
Published: May 2009

Organic fluorescent molecules are infiltrated in the channels of zeolite L nanocrystals, thus creating organic–inorganic fluorescent nanoparticles. Combined with dielectric matrices, these fluorescent nanopigments open the way to the realization of novel optical devices. In this paper, the optical measurement of the quantum yield of fluorescent zeolites by means of a precise and reliable diffuse reflectance technique is presented. Several possible factors that may affect the fluorescence quantum yield are also investigated.
Formation of Hierarchically Structured Thin Films
Authors: Wang Ming , Comrie Jean E. , Bai Yunpeng , He Ximin , Guo Shaoyun , Huck Wilhelm T. S.
Published: May 2009

Here, we report the preparation of hierarchically structured polymer brushes with well‐defined geometries via multiple step microcontact printing (MS‐µCP) of inks containing different ratios of initiator‐terminated thiols and non‐reactive alkylthiols. Thick (and dense), polymer brushes grew from self‐assembled monolayers (SAMs) with high concentration of initiator‐terminated thiols, and these brushes exhibited high chemical etch‐resistance, compared to thin (and less dense), brushes grown from more dilute initiator‐terminated SAMs. Upon etching, patterned crosslinking polymer brush films decorated with thin layers of Au, could be lifted off the surface to form geometrically well‐defined free‐standing hierarchical films. These polymer brush films showed interesting buckling instabilities when compressed. Areas with different brush thicknesses and Au backing showed markedly different buckling behavior, leading to unusual patterns of wrinkles with different wavelengths and orientations toward the force field.
Unraveling Deterministic Mesoscopic Polarization Switching Mechanisms: Spatially Resolved Studies of a Tilt Grain Boundary in Bismuth Ferrite
Authors: Rodriguez Brian J. , Choudhury Samrat , Chu Y. H. , Bhattacharyya Abhishek , Jesse Stephen , Seal Katyayani , Baddorf Arthur P. , Ramesh R. , Chen Long‐Qing , Kalinin Sergei V.
Published: May 2009

The deterministic mesoscopic mechanism of ferroelectric domain nucleation is probed at a single atomically‐defined model defect: an artificially fabricated bicrystal grain boundary (GB) in an epitaxial bismuth ferrite film. Switching spectroscopy piezoresponse force microscopy (SS‐PFM) is used to map the variation of local hysteresis loops at the GB and in its immediate vicinity. It is found that the the influence of the GB on nucleation results in a slight shift of the negative nucleation bias to larger voltages. The mesoscopic mechanisms of domain nucleation in the bulk and at the GB are studied in detail using phase‐field modeling, elucidating the complex mechanisms governed by the interplay between ferroelectric and ferroelastic wall energies, depolarization fields, and interface charge. The combination of phase‐field modeling and SS‐PFM allows quantitative analysis of the mesoscopic mechanisms for polarization switching, and hence suggests a route for unraveling the mechanisms of polarization switching at a single defect level and ultimately optimizing materials properties through microstructure engineering.
Surface Design in Solid‐State Dye Sensitized Solar Cells: Effects of Zwitterionic Co‐adsorbents on Photovoltaic Performance
Authors: Wang Mingkui , Grätzel Carole , Moon Soo‐Jin , Humphry‐Baker Robin , Rossier‐Iten Nathalie , Zakeeruddin Shaik M. , Grätzel Michael
Published: May 2009

In solid‐state dye sensitized solar cells (SSDSCs) charge recombination at the dye‐hole transporting material interface plays a critical role in the cell efficiency. For the first time we report on the influence of dipolar co‐adsorbents on the photovoltaic performance of sensitized hetero‐junction solar cells. In the present study, we investigated the effect of two zwitterionic butyric acid derivatives differing only in the polar moiety attached to their common 4 carbon‐chain acid, i.e., 4‐guanidinobutyric acid (GBA) and 4‐aminobutyric acid (ABA). These two molecules were implemented as co‐adsorbents in conjunction with Z907Na dye on the SSDSC. It was found that a Z907Na/GBA dye/co‐adsorbent combination increases both the open circuit voltage (Voc) and short‐circuit current density (Jsc) as compared to using Z907Na dye alone. The Z907Na/ABA dye/co‐adsorbent combination increases the Jsc. Impedance and transient photovoltage investigations elucidate the cause of these remarkable observations.
Synthesis of Microporous Carbon Nanofibers and Nanotubes from Conjugated Polymer Network and Evaluation in Electrochemical Capacitor
Authors: Feng Xinliang , Liang Yanyu , Zhi Linjie , Thomas Arne , Wu Dongqing , Lieberwirth Ingo , Kolb Ute , Müllen Klaus
Published: May 2009

One‐dimensional fibers and tubes are constructed through the oriented carbon‐carbon cross‐linking reactions towards rigid conjugated polymer networks. As the result, a template‐free and one‐step synthesis of CNTs and CNFs is achieved through a simple carbonization of the as‐formed carbon‐rich tubular and fiberlike polyphenylene precursors under argon. Microporous CNTs and CNFs with a surface area up to 900 m2 g–1 are obtained, together with HR‐TEM characterizations indicating the formation of intrinsic microporous structure in these rigid carbon‐rich networks. The primary electrochemical experiments reveal their promising applications as advanced electrodes in electrochemical double‐layered capacitor (EDLC).
Synthesis of Microspheres as Versatile Functional Scaffolds for Materials Science Applications
Authors: Barner Leonie
Published: May 2009

Functional polymeric microspheres are of great interest as they have high potential as functional scaffolds in material science applications. Highly cross‐linked poly(divinyl benzene) (pDVB) microspheres can be synthesized via the precipitation polymerization technique. Recently, various methods of controlled polymerization techniques (e.g., atom transfer radical polymerization (ATRP), reversible addition fragmentation chain transfer (RAFT), and anionic ring‐opening polymerization (AROP)) and highly orthogonal conjugation methods (e.g., copper‐catalyzed Huisgen 1,3‐dipolar cycloaddition of azides and terminal alkynes (CuAAc), thiol‐ene addition and RAFT hetero Diels–Alder cycloaddition (RAFT‐HDA)) have been applied to functionalize microspheres via the “grafting from” and “grafting to” approaches. The synthesis of pDVB microspheres, their subsequent modification via grafting of polymer strands to the surface, and the characterization of the obtained functional particles are reviewed.
Alternation of Chemoselective Control in Stille–Heck and Heck–Stille Reaction Sequences
Authors: Masters Kye‐Simeon , Flynn Bernard L.
Published: May 2009

The communication by Kye‐Simeon Masters and Bernard L. Flynn in Issue 4, 2009, pp. 530–536 (DOI: 10.1002/adsc.200800678), should have appeared in this issue dedicated to Professor Armin de Meijere. It was published in Issue 4, 2009, by mistake. On the title page, below the received and publication dates, the following dedication should appear: “Dedicated to Professor Armin de Meijere on the occasion of his 70th birthday.” The editorial office apologizes for this mistake.
Innentitelbild: Umwandlung der absoluten Konfiguration einzelner Adsorbatkomplexe (Angew. Chem. 22/2009)
Authors: Parschau Manfred , Passerone Daniele , Rieder Karl‐Heinz , Hug Hans J. , Ernst Karl‐Heinz
Published: May 2009

Falsche Händigkeit? Kein Problem! K.‐H. Ernst et al. beschreiben in ihrer Zuschrift auf S. 4125 ff. eine Prozedur zur Konfigurationsumkehr einzelner chiraler Adsorbate. Durch inelastisch tunnelnde Elektronen aus einer Rastertunnelmikroskopspitze werden Molekülschwingungen angeregt, die dann Aktionen wie Rotation, Translation oder die Inversion der absoluten Konfiguration bewirken.

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Highlights in Colloid Science.Edited by D. Platikanov and D. Exerowa.
Authors: Fuhrhop Jürgen‐Hinrich
Published: May 2009

Wiley‐VCH, Weinheim 2009. 306 pp., hardcover, 129.00 €.—ISBN 978‐3527320370

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Metal Oxide Catalysis.1+2. Edited by S. David Jackson and Justin S. J. Hargreaves.
Authors: Thornton Geoff
Published: May 2009

Wiley‐VCH, Weinheim 2008. 866 pp., hardcover € 279.00.—ISBN 978‐3527318155

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Cover Picture: Photoprogrammable Organic Light‐Emitting Diodes (Angew. Chem. Int. Ed. 22/2009)
Authors: Zacharias Philipp , Gather Malte C. , Köhnen Anne , Rehmann Nina , Meerholz Klaus
Published: May 2009

Programmable organic light‐emitting diodes: UV irradiation converts an oxetane‐functionalized dithienylethene derivative from its colorless open form into a dark blue closed form, while visible light reverses the reaction. In the Communication on page 4038 ff., K. Meerholz and co‐workers describe a reversibly switchable organic light‐emitting diode based on this principle.

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Seasonal changes in distribution of Hector's dolphin at Banks Peninsula, New Zealand: implications for protected area design
Authors: Rayment William , Dawson Steve , Slooten Elisabeth
Published: May 2009

The efficacy of protected areas for wildlife management is largely dependent on appropriate design. It is therefore crucial that the distribution of target species is well understood.

The Banks Peninsula Marine Mammal Sanctuary (BPMMS) was designed to protect Hector's dolphins from bycatch in gillnets. However, the Banks Peninsula dolphin population is likely to be still declining, partly due to continued bycatch outside the boundaries of the BPMMS.

A three year series of aerial line‐transect surveys around Banks Peninsula was carried out to investigate seasonal changes in distribution of Hector's dolphins out to 20 nautical miles (37 km) from the coast.

Dolphin sightings were concentrated close to shore in shallow water in summer, but were more evenly distributed throughout the study area in winter. A greater proportion of dolphins were sighted outside the 4 nautical miles (7.4 km) offshore boundary of the BPMMS in winter (mean=56%) than in summer (mean=19%) (G=88.25, df=1, P<0.001).

Partial Mantel tests revealed the effects of distance offshore and depth on dolphin occurrence while controlling for spatial autocorrelation and multicollinearity within the data. Distance offshore had the strongest and most consistent effect on dolphin presence, while depth had a strong effect in summer only.

It is proposed that restrictions on gillnetting around Banks Peninsula must be extended in order to reduce bycatch of Hector's dolphins to a sustainable level, and that a new offshore boundary of the BPMMS would be best defined by distance from the coast. Copyright © 2009 John Wiley & Sons, Ltd.
A Lorentz model for weak magnetic field bioeffects: Part I—Thermal noise is an essential component of AC/DC effects on bound ion trajectory
Authors: Muehsam David J. , Pilla Arthur A.
Published: May 2009

We have previously employed the Lorentz–Langevin model to describe the effects of weak exogenous magnetic fields via the classical Lorentz force on a charged ion bound in a harmonic oscillator potential, in the presence of thermal noise forces. Previous analyses predicted that µT‐range fields give rise to a rotation of the oscillator orientation at the Larmor frequency and bioeffects were based upon the assumption that the classical trajectory of the bound charge itself could modulate a biochemical process. Here, it is shown that the thermal component of the motion follows the Larmor trajectory. The results show that the Larmor frequency is independent of the thermal noise strength, and the motion retains the form of a coherent oscillator throughout the binding lifetime, rather than devolving into a random walk. Thermal equilibration results in a continual increase in the vibrational amplitude of the rotating oscillator towards the steady‐state amplitude, but does not affect the Larmor orbit. Thus, thermal noise contributes to, rather than inhibits, the effect of the magnetic field upon reactivity. Expressions are derived for the ensemble average of position and the velocity of the thermal component of the oscillator motion. The projection of position and velocity onto a Cartesian axis measures the nonuniformity of the Larmor trajectory and is illustrated for AC and combined AC/DC magnetic fields, suggesting a means of interpreting resonance phenomena. It is noted that the specific location and height of resonances are dependent upon binding lifetime and initial AC phase. Bioelectromagnetics 30:462–475, 2009. © 2009 Wiley‐Liss, Inc.
Low‐frequency conductivity tensor of rat brain tissues inferred from diffusion MRI
Authors: Sekino Masaki , Ohsaki Hiroyuki , Yamaguchi‐Sekino Sachiko , Iriguchi Norio , Ueno Shoogo
Published: May 2009

Conductivity tensor maps of the rat brain were obtained using diffusion magnetic resonance imaging (MRI). Signal attenuations in the cortex and the corpus callosum were measured using the stimulated echo acquisition mode (STEAM) sequence with b factors up to 6000 s/mm2. Our previously published method was improved to infer 3 × 3 conductivity tensor at the low‐frequency limit. The conductivity tensor of the tissue was inferred from the fast component of the diffusion tensor and a fraction of the fast component. The mean conductivity (MC) of the cortex and the corpus callosum was 0.52 and 0.62 S/m, respectively. Diffusion‐weighted images were obtained with b factors up to 4500 s/mm2. Conductivity tensor images were calculated from the fast diffusion tensor images. Tissues with highly anisotropic cellular structures, such as the corpus callosum, the internal capsule, and the trigeminal nerve, exhibited high anisotropy in conductivity. The resulting values corresponded to conductivities at the low‐frequency limit because our method assumed electric currents flowing only through extracellular fluid. Bioelectromagnetics 30:489–499, 2009. © 2009 Wiley‐Liss, Inc.
Multiphoton imaging of host‐pathogen interactions
Authors: Melican Keira , Richter‐Dahlfors Agneta
Published: May 2009

Studying the events that occur when a pathogen comes into contact with its host is the basis of the field of infection biology. Over the years, work in this area has revealed many facets of the infection process, including attachment, invasion and colonization by the pathogen, and of the host responses, such as the triggering of the immune system. Recent advancements in imaging technologies, such as multiphoton microscopy (MPM), mean that the field is in the process of taking another big leap forward. MPM allows for cellular‐level visualization of the real‐time dynamics of infection within the living host. The use of live animal models means that all the interplaying factors of an infection, such as the influences of the immune, lymphatic and vascular systems, can be accounted for. This review outlines the developing field of MPM in pathogen‐host interactions, highlighting a number of new insights that have been ‘brought to light’ using this technique.
Deciphering interactions of the aminoglycoside phosphotransferase(3′)‐IIIa with its ligands
Authors: Wu Lingzhi , Serpersu Engin H.
Published: May 2009

Aminoglycoside phosphotransferase(3′)‐IIIa (APH) is the enzyme with broadest substrate range among the phosphotransferases that cause resistance to aminoglycoside antibiotics. In this study, the thermodynamic characterization of interactions of APH with its ligands are done by determining dissociation constants of enzyme–substrate complexes using electron paramagnetic resonance and fluorescence spectroscopy. Metal binding studies showed that three divalent cations bind to the apo‐enzyme with low affinity. In the presence of AMPPCP, binding of the divalent cations occurs with 7‐to‐37‐fold higher affinity to three additional sites dependent on the presence and absence of different aminoglycosides. Surprisingly, when both ligands, AMPPCP and aminoglycoside, are present, the number of high affinity metal binding sites is reduced to two with a 2‐fold increase in binding affinity. The presence of divalent cations, with or without aminoglycoside present, shows only a small effect (<3‐fold) on binding affinity of the nucleotide to the enzyme. The presence of metal–nucleotide, but not nucleotide alone, increases the binding affinity of aminoglycosides to APH. Replacement of magnesium (II) with manganese (II) lowered the catalytic rates significantly while affecting the substrate selectivity of the enzyme such that the aminoglycosides with 2′‐NH2 become better substrates (higher Vmax) than those with 2′‐OH. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 801–809, 2009.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Cellulose hydrolysis in evolving substrate morphologies II: Numerical results and analysis
Authors: Zhou Wen , Hao Zhiqian , Xu Ying , Schüttler Heinz‐Bernd
Published: May 2009

Numerical simulation results are presented for a cellulose hydrolysis model which incorporates both the enzymatic glucan chain fragmentation kinetics and the hydrolytic substrate morphology evolution within the general framework of our companion article I. To test the local Poisson (LP) approximation employed in the site number formalism of I, we numerically compare it to the corresponding exact chain number formalism of I. The LP results agree to very high accuracy with the exact chain number kinetics, assuming realistic parameters. From simulations of different types of random and non‐random model morphologies, we then show that the details of the random substrate morphology distribution, and its hydrolytic time evolution, profoundly affect the hydrolysis kinetics. Essential, likely very general, experimentally testable features of such morphology‐based hydrolysis models are (i) the existence of two distinct time scales, associated with the hydrolysis of the outermost surface‐exposed cellulose chains and, respectively, of the entire substrate; (ii) a strongly morphology‐dependent hydrolysis slow‐down effect, which has also been observed in previous experimental work. Our results also suggest that previously proposed non‐morphologic chain fragmentation models can only be applied to describe the hydrolytic short‐time behavior in the low enzyme limit. Further experiments to test our modeling framework and its potential applications to the optimization of the hydrolytic conversion process are discussed. Biotechnol. Bioeng. 2009; 104: 275–289 © 2009 Wiley Periodicals, Inc.
Intermediates in the Autoxidation of Nitrogen Monoxide
Authors: Galliker Benedikt , Kissner Reinhard , Nauser Thomas , Koppenol Willem H.
Published: May 2009

ONOO. is an important intermediate in the autoxidation of nitrogen monoxide by dioxygen. A formerly unknown red isomer of N2O4, ONOONO (see figure), formed in 2‐methylbutane at 113 K from nitrogen monoxide and dioxygen, is converted to O2NNO2 upon warming.

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We have identified two intermediates in the autoxidation of NO.: ONOO., which was detected by EPR spectroscopy at 295 K and atmospheric pressure in the gas phase, and ONOONO, a red substance produced at 113 K in 2‐methylbutane. The red compound is diamagnetic and absorbs maximally at 500 nm. The ONOONO intermediate is unstable above the melting point of 2‐methylbutane and rapidly converts to O2NNO2. From the semiquantitative determination of mole fractions present in the gas phase by EPR spectroscopy, we estimated the rate constants for the steps that lead to ONOO. and ONOONO, from the known overall rate constant of the autoxidation reaction, by assuming that a quasi‐stationary mechanism applies. The rate constant for the rate‐determining formation of ONOO. is about 3.1×10−18 cm3 molecule−1 s−1 (or 80 s−1 in mole fractions), the dissociation rate constant of ONOO. is about 6.5×103 s−1, and ONOONO is formed with a rate constant of k=7.7×10−14 cm3 molecule−1 s−1 (1.9×106 s−1 in mole fractions). From these constants, we estimate that the equilibrium constant for the formation of ONOO. from NO. and O2 (K) is 4.8×10−22 cm3 molecule−1 (1.2×10−2), and, therefore, ΔG=+11.0 kJ mol−1. In water, the Gibbs energy change is close to zero. The presence of ONOO. at steady‐state concentrations under dioxygen excess may be important not only for reactions in the atmosphere, but especially for reactions in aerosols and biological environments, because the rate constant for formation in solution is higher than that in the gas phase, and, therefore, the half‐life of ONOO. is longer.
Cortactin: Coordinating adhesion and the actin cytoskeleton at cellular protrusions
Authors: Ren Gang , Crampton Matthew S. , Yap Alpha S.
Published: May 2009

It has long been recognized that adhesion receptors cooperate with the cytoskeleton during morphogenesis, tissue remodeling and homeostasis. But how this occurs is less well‐understood. A host of cytoskeletal regulators have been reported to have functional and biochemical linkage with adhesion receptors. The challenge remains to find functionally‐coherent patterns within this increasingly large corpus of molecular information. In this review we discuss one approach, to identify distinctive functional modules that contribute to different adhesive processes. We illustrate this by considering Arp2/3‐driven surface protrusion, which is utilized at both integrin‐based cell‐matrix adhesions and cadherin‐based cell‐cell adhesions. We further argue that regulatory proteins, such as cortactin, serve to coordinate the molecular components of this protrusive apparatus into a cohesive module. Cell Motil. Cytoskeleton 2009. © 2009 Wiley‐Liss, Inc.
Design and Discovery of Plasmepsin II Inhibitors Using an Automated Workflow on Large‐Scale Grids
Authors: Degliesposti Gianluca , Kasam Vinod , Da Costa Ana , Kang Hee‐Kyoung , Kim Nahyun , Kim Do‐Won , Breton Vincent , Kim Doman , Rastelli Giulio
Published: May 2009

Novel and potent inhibitors of Plasmodium falciparum plasmepsin II were identified by post‐processing the results of a docking screening with BEAR, a recently reported procedure for the refinement and rescoring of docked ligands in virtual screening. FRET substrate degradation assays performed on the 30 most promising compounds resulted in 26 inhibitors with IC50 values ranging from 4.3 nM to 1.8 μM.

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Herein we report the discovery of novel and potent inhibitors of Plasmodium falciparum plasmepsin II using GRID computing infrastructures. These compounds were identified by post‐processing the results of a large docking screen of commercially available compounds using an automated procedure based on molecular dynamics refinement and binding free‐energy estimation using MM‐PBSA and MM‐GBSA. Among the best‐scored compounds, four highly populated and promising chemical classes were identified: N‐alkoxyamidines, guanidines, amides, and ureas and thioureas. Thirty hit compounds representative of each class were selected on the basis of their favourable binding free energies and molecular interactions with key active site residues. These were experimentally validated using an inhibition assay based on FRET substrate degradation. Remarkably, 26 of the 30 tested compounds proved to be active as plasmepsin II inhibitors, with IC50 values ranging from 4.3 nM to 1.8 μM.
N‐Formylation of Amines via the Aerobic Oxidation of Methanol over Supported Gold Nanoparticles
Authors: Ishida Tamao , Haruta Masatake
Published: May 2009

Dress code: formyl. Gold nanoparticles supported on NiO catalyze the one‐pot N‐formylation of amines with methanol and molecular oxygen to produce formamide at a selectivity of 90 %. This process generates methyl formate in situ, followed by reaction with amines.

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Integrating glycaemic variability in the glycaemic disorders of type 2 diabetes: a move towards a unified glucose tetrad concept
Authors: Monnier Louis , Colette Claude , Owens David R.
Published: May 2009

The high incidence of atherosclerosis and cardiovascular disease (CVD) is the leading cause of morbidity and mortality among patients with diabetes. Evidence is accumulating that postprandial hyperglycaemia is an independent risk factor for diabetes‐associated complications and mortality, and that worsening diabetes control is characterized by postprandial glucose (PPG) deterioration preceding an impairment in fasting glucose levels. Postprandial and general glucose fluctuations play a major role in activating oxidative stress, leading to the endothelial dysfunction, one of the mechanisms responsible for vascular complications. Therefore, the management of PPG is key for any strategy used in the monitoring and treatment of diabetes. We recommend that any strategy aimed at controlling the glycaemic disorders associated with type 2 diabetes, and limiting the risk of complications, should target the ‘glucose tetrad’, which comprises the following components: HbA1c, fasting and postprandial plasma glucose, and markers of glycaemic variability, such as the mean amplitude of glycaemic excursions (MAGE) index. This brings together, in a simple, unified concept, the conventional markers (HbA1c and fasting glucose) and the more recently recognized markers of glycaemic control (PPG excursions and acute glycaemic variability). Copyright © 2009 John Wiley & Sons, Ltd.
Pulse pressure and cardiovascular autonomic neuropathy according to duration of type 1 diabetes
Authors: Philips J. C. , Marchand M. , Scheen A. J.
Published: May 2009

Background

To evaluate changes in pulse pressure (PP) and markers of cardiovascular autonomic neuropathy (CAN) according to duration of type 1 diabetes mellitus (T1DM).

Methods

This cross‐sectional controlled study evaluated 159 diabetic patients during a 3‐min posture test (standing–squatting–standing) with continuous measurement of systolic (SBP), diastolic (DBP) and mean (MBP) blood pressure by a Finapres device. Arterial stiffness was indirectly assessed by PP and the slope of PP as a function of MBP calculated during the whole 3‐min test. CAN was assessed by the expiration/inspiration pulse interval ratio (E/I R‐R ratio) during deep breathing and by three indices measured during the squatting test. Patients were divided into four groups according to diabetes duration (<10 years, 11–20 years, 21–30 years and > 30 years from group 1 to group 4, respectively) and compared with age‐matched non‐diabetic subjects.

Results

PP progressively increased (p < 0.0001) and PP/MBP decreased (p < 0.0005) according to T1DM duration, whereas these parameters remained almost unchanged in age‐matched control subjects. E/I ratio (p < 0.0001) and baroreflex gain (p < 0.0005) progressively decreased with T1DM duration. The parasympathetic index (squatting test vagal ratio—SqTv) significantly increased (p < 0.0001), whereas the sympathetic index (squatting test sympathetic ratio—SqTs) only tended to decrease (p = 0.12) according to diabetes duration. No such changes in CAN indices were observed in the non‐diabetic population.

Conclusions

PP increased according to T1DM duration in an age range where PP remained almost stable in controls, in agreement with accelerated arterial stiffening due to chronic hyperglycaemia. The baroreflex gain decreased and other indices of CAN also deteriorated with diabetes duration, more so indices reflecting parasympathetic rather than sympathetic dysfunction. Copyright © 2009 John Wiley & Sons, Ltd.
Weight control behaviors among overweight, normal weight and underweight adolescents in Palestine: Findings from the national study of Palestinian schoolchildren (HBSC‐WBG2004)
Authors: Al Sabbah Haleama , Vereecken Carine , Abdeen Ziad , Kelly Colette , Ojala Kristiina , Németh Ágnes , Ahluwalia Namanjeet , Maes Lea
Published: May 2009

Objective:

The objective of the study is to examine the relationship between weight‐control behaviors and self‐reported sociodemographic characteristics, weight status, and perception of body weight in a large, representative sample of adolescents in the West Bank and Gaza Strip territories of Palestine.

Method:

Self‐report measures of sociodemographic characteristics, body weight perception, height and weight, and weight‐control behaviors were completed by 8,885 male and female students aged 12–18 years from 405 randomly selected schools as part of the 2003/2004 Palestinian Health Behavior in School‐aged Children Study (HBSC).

Results:

In both genders, dieting to lose weight was common among adolescents and significantly higher among overweight than among underweight or normal weight adolescents. Extreme weight‐control behaviors (vomiting, diet pills, or laxatives) and smoking were more common among boys than girls, and extreme weight‐control behaviors were particularly common among underweight boys. Older adolescents were less likely than younger adolescents to engage in weight‐control behaviors. Perception of body weight as too fat was an influential factor in following an unhealthy diet to lose weight.

Discussion:

Practices to control weight, particularly extreme and unhealthy weight‐control behaviors, are common among adolescents in the Palestinian territories. These findings suggest the need to design appropriate prevention and early intervention programs for adolescents in Palestine. © 2009 by Wiley Periodicals, Inc. Int J Eat Disord 2010
Selective Synthesis of Isoquinolin‐3‐one Derivatives Combining Pd‐Catalysed Aromatic Alkylation/Vinylation with Addition Reactions: The Beneficial Effect of Water
Authors: Ferraccioli Raffaella , Forni Alessandra
Published: May 2009

The three‐component, palladium/norbornene‐catalysed reaction of 1, haloamides 2 and properly substituted olefins 3 performed in DMF/water at 80 °C selectively gave 5 and 6 through three‐ and four‐bond‐forming reactions, respectively. The presence of water was crucial to obtain products in fair to good yields. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Oxathiocoraline: Lessons to be Learned from the Synthesis of ComplexN‐Methylated Depsipeptides
Authors: Bayó‐Puxan Núria , Tulla‐Puche Judit , Albericio Fernando
Published: May 2009

Investigations into the synthesis of oxathiocoraline, a bicyclic depsipeptide withC2symmetry, revealed a number of unexpected side‐reactions that could not be circumvented by classical or standard means. This cyclodepsipeptide has a large number ofN‐methyl amino acids coexisting with two ester bonds and also shows a branched structure; these features hinder its synthesis. In addition, complexity is further increased because of the presence of a large number of non‐commercially available cysteines and heterocyclic moieties. Here we describe the general points that should be addressed when attempting the synthesis of a cyclodepsipeptide, such as strategies to prevent or minimize diketopiperazine formation, β‐elimination, and oxidation byproducts. The optimum design includes a suitable solid support, the choice of the best starting point for the synthesis (first amino acid to anchor to the resin) and a set of compatible and/or protecting groups and coupling reagents.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Electrocatalytic Oxidation and Determination of Cysteamine by Poly‐N,N‐dimethylaniline/Ferrocyanide Film Modified Carbon Paste Electrode
Authors: Ojani Reza , Raoof Jahan‐Bakhsh , Zarei Ebrahim
Published: May 2009

Functionalized poly‐N,N‐dimethylaniline film was prepared by adsorption of ferrocyanide onto the polymer forming at the surface of carbon paste electrode (CPE) in aqueous solution by using potentiostatic method. The electrocatalytic ability of poly‐N,N‐dimethylaniline/ferrocyanide film modified carbon paste electrode (PDMA/FMCPE) was demonstrated by oxidation of cysteamine. Cyclic voltammetry and chronoamperometry techniques were used to investigate this ability. Results showed that pH 7.00 is the most suitable for this purpose. It is found that the catalytic reaction rate constant, (kh), is equal to 2.142×103 M−1 s−1 by the data of chronoamperometry. The catalytic reduction peak current was linearly dependent on the cysteamine concentration and the linearity range obtained was 8.00×10−5 M–1.14×10−2 M. Detection limit was determined 7.97×10−5 M (2σ). This method has been successfully employed for quantification of cysteamine in real sample.
Electrochemical Detection of DNA Melting Curves by Means of Heated Biosensors
Authors: Surkus Annette‐Enrica , Flechsig Gerd‐Uwe
Published: May 2009

This article reports about the detection of DNA melting curves at heated electrochemical biosensors. Osmium tetroxide‐bipyridine‐labeled target oligonucleotides are hybridized with probe oligonucleotides immobilized on gold electrodes. Then, the gold electrode is successively heated in order to measure a complete melting curve consisting of alternating current voltammetric signals. Melting temperatures ϑm, determined at various ionic strengths and in dependence on different numbers of base pair mismatches, have been compared with those obtained by means of UV spectrophotometry. The proposed method holds great promise for the fast and easy parallel detection of nucleic acids sequences on selectively heated electrode arrays. A stringent hybridization temperature can be easily adjusted in order to discriminate base pair mismatches.
Hippocampal shape analysis for Alzheimer's disease using an efficient hypothesis test and regularized discriminative deformation
Authors: Zhou Luping , Lieby Paulette , Barnes Nick , Réglade‐Meslin Chantal , Walker Janine , Cherbuin Nicolas , Hartley Richard
Published: May 2009

In this article, we present a framework to perform statistical shape analysis for segmented hippocampi, including an efficient permutation test for detecting subtle class differences, and a regularized discriminative direction method for visualizing the shape discrepancy. Fisher permutation and bootstrap tests are preferred to traditional hypothesis tests which impose assumptions on the distribution of the samples. In this article, an efficient algorithm is adopted to rapidly perform the exact tests. We extend this algorithm to multivariate data by projecting the shape descriptors onto an informative direction that preserves the original discriminative information as much as possible to generate a scalar test statistic. This informative direction is further used to seek a discriminative direction to isolate the discriminative shape difference between classes from the individual variability. Compared with existing methods, the discriminative direction used in this article is regularized by requiring that the shapes deformed along it respect the underlying shape distribution as well as reflecting the essential shape differences between two populations. Hence, a more accurate localization of difference is produced. We apply our methods to analyze the hippocampal shapes for controls and subjects with Alzheimer's disease from the publicly available OASIS MRI database. We show how to localize the shape differences between the two classes. © 2009 Wiley‐Liss, Inc.