bluuebunny/crossref_metadata_2025 huggingface dataset:
MAIT cell clonal expansion and TCR repertoire shaping in human volunteers challenged with Salmonella Paratyphi A
Authors: Howson Lauren J. , Napolitani Giorgio , Shepherd Dawn , Ghadbane Hemza , Kurupati Prathiba , Preciado-Llanes Lorena , Rei Margarida , Dobinson Hazel C. , Gibani Malick M. , Teng Karen Wei Weng , Newell Evan W. , Veerapen Natacha , Besra Gurdyal S. , Pollard Andrew J. , Cerundolo Vincenzo
Published: January 2018

Mucosal-associated invariant T (MAIT) cells are innate-like T cells that can detect bacteria-derived metabolites presented on MR1. Here we show, using a controlled infection of humans with live Salmonella enterica serovar Paratyphi A, that MAIT cells are activated during infection, an effect maintained even after antibiotic treatment. At the peak of infection MAIT cell T-cell receptor (TCR)β clonotypes that are over-represented prior to infection transiently contract. Select MAIT cell TCRβ clonotypes that expand after infection have stronger TCR-dependent activation than do contracted clonotypes. Our results demonstrate that host exposure to antigen may drive clonal expansion of MAIT cells with increased functional avidity, suggesting a role for specific vaccination strategies to increase the frequency and potency of MAIT cells to optimize effector function.
Atmospheric CO2 effect on stable carbon isotope composition of terrestrial fossil archives
Authors: Hare Vincent J. , Loftus Emma , Jeffrey Amy , Ramsey Christopher Bronk
Published: January 2018

The 13C/12C ratio of C3 plant matter is thought to be controlled by the isotopic composition of atmospheric CO2 and stomatal response to environmental conditions, particularly mean annual precipitation (MAP). The effect of CO2 concentration on 13C/12C ratios is currently debated, yet crucial to reconstructing ancient environments and quantifying the carbon cycle. Here we compare high-resolution ice core measurements of atmospheric CO2 with fossil plant and faunal isotope records. We show the effect of pCO2 during the last deglaciation is stronger for gymnosperms (−1.4 ± 1.2‰) than angiosperms/fauna (−0.5 ± 1.5‰), while the contributions from changing MAP are −0.3 ± 0.6‰ and −0.4 ± 0.4‰, respectively. Previous studies have assumed that plant 13C/12C ratios are mostly determined by MAP, an assumption which is sometimes incorrect in geological time. Atmospheric effects must be taken into account when interpreting terrestrial stable carbon isotopes, with important implications for past environments and climates, and understanding plant responses to climate change.
PERK-mediated translational control is required for collagen secretion in chondrocytes
Authors: Hisanaga Satoshi , Miyake Masato , Taniuchi Shusuke , Oyadomari Miho , Morimoto Masatoshi , Sato Ryosuke , Hirose Jun , Mizuta Hiroshi , Oyadomari Seiichi
Published: January 2018

As chondrocytes are highly secretory and they experience a variety of stresses, physiological unfolded protein response (UPR) signalling is essential for extracellular matrix (ECM) secretion and chondrogenesis. In the three branches of the UPR pathway, PERK governs the translational attenuation and transcriptional upregulation of amino acid and redox metabolism and induction of apoptosis. It was previously demonstrated that a defect of the PERK branch of the UPR signalling pathway causes the accumulation of unfolded proteins, leading to cell death without perturbing endoplasmic reticulum (ER)-to-Golgi transport in pancreatic β cells. However, little is known about the role of PERK in chondrocytes. In this study, we found that PERK signalling is activated in chondrocytes, and inhibition of PERK reduces collagen secretion despite causing excessive collagen synthesis in the ER. Perk
−/−
mice displayed reduced collagen in articular cartilage but no differences in chondrocyte proliferation or apoptosis compared to the findings in wild-type mice. PERK inhibition increases misfolded protein levels in the ER, which largely hinder ER-to-Golgi transport. These results suggest that the translational control mediated by PERK is a critical determinant of ECM secretion in chondrocytes.
Rate after-effects fail to transfer cross-modally: Evidence for distributed sensory timing mechanisms
Authors: Motala Aysha , Heron James , McGraw Paul V. , Roach Neil W. , Whitaker David
Published: January 2018

Accurate time perception is critical for a number of human behaviours, such as understanding speech and the appreciation of music. However, it remains unresolved whether sensory time perception is mediated by a central timing component regulating all senses, or by a set of distributed mechanisms, each dedicated to a single sensory modality and operating in a largely independent manner. To address this issue, we conducted a range of unimodal and cross-modal rate adaptation experiments, in order to establish the degree of specificity of classical after-effects of sensory adaptation. Adapting to a fast rate of sensory stimulation typically makes a moderate rate appear slower (repulsive after-effect), and vice versa. A central timing hypothesis predicts general transfer of adaptation effects across modalities, whilst distributed mechanisms predict a high degree of sensory selectivity. Rate perception was quantified by a method of temporal reproduction across all combinations of visual, auditory and tactile senses. Robust repulsive after-effects were observed in all unimodal rate conditions, but were not observed for any cross-modal pairings. Our results show that sensory timing abilities are adaptable but, crucially, that this change is modality-specific - an outcome that is consistent with a distributed sensory timing hypothesis.
LPS-induced Vitamin D Receptor Decrease in Oral Keratinocytes Is Associated With Oral Lichen Planus
Authors: Zhao Bin , Li Ran , Yang Fang , Yu Feiyan , Xu Na , Zhang Fang , Ge Xuejun , Du Jie
Published: January 2018

The suppressive function of vitamin D on oral lichen planus (OLP) have been documented previously. Vitamin D receptor (VDR) expression is down-regulated in OLP, but the molecular mechanism of its decrease and the related anti-inflammatory contributor of epithelial VDR signaling is unclear. Herein, we demonstrated that lipopolysaccharide (LPS) remarkedly down-regulated VDR expression of keratinocytes, and the reduced regulation was dependent on tumor necrosis factor alpha (TNFα)-miR-346 pathway. In human specimen studies, VDR levels of oral mucosal epithelia from OLP patients decreased substantially accompanied with robust TNFα and miR-346 induction, compared to the normal tissues. In addition, vitamin D/VDR signaling inhibited LPS-induced p53-upregulated modulator of apoptosis (PUMA) induction in keratinocytes via impeding nuclear factor-κB (NF-κB) activation, resulting in keratinocytes apoptosis reduction. Importantly, PUMA activity was up-regulated strongly in diseased epithelium, reversely correlated with VDR expression. Totally, our data indicate that LPS is responsible for VDR downregulation in oral keratinocytes, which is associated with OLP development.
The Static Magnetic Field Remotely Boosts the Efficiency of Doxorubicin through Modulating ROS Behaviors
Authors: Hajipour Verdom Behnam , Abdolmaleki Parviz , Behmanesh Mehrdad
Published: January 2018

Exposure to magnetic field (MF) can affect cellular metabolism remotely. Cardio-toxic effects of Doxorubicin (DOXO) have limited clinical uses at high dose. MF due to its effect on reactive oxygen species (ROS) lifetime, may provide a suitable choice to boost the efficacy of this drug at low dose. Here, we investigated the potential effects of homogenous static magnetic field (SMF) on DOXO-induced toxicity and proliferation rate of cancer cells. The results indicated that SMF similar to DOXO decreased the cell viability as well as the proliferation rate of MCF-7 and HFF cells. Moreover, combination of 10 mT SMF and 0.1 µM DOXO decreased the viability and proliferation rate of cancer and normal cells in a synergetic manner. In spite of high a GSH level in cancer cell, SMF boosts the generation and lifetime of ROS at low dose of DOXO, and overcame to GSH mediated drug resistance. The results also confirmed that SMF exposure decreased 50% iron content of cells, which is attributed to iron homeostasis. In conclusion, these findings suggest that SMF can decrease required dose of chemotherapy drugs such as DOXO and thereby decrease their side effect.
Separation and characterization of cellulose nanocrystals by multi-detector asymmetrical-flow field-flow fractionation
Authors: Mukherjee Arnab , Hackley Vincent A.
Published: January 2018

A detailed method for controlled fractionation of polydisperse cellulose nanocrystals enables real-time on-line analysis of size, molar mass and shape factor.
A “turn-on” fluorescence sensor for ascorbic acid based on graphene quantum dots via fluorescence resonance energy transfer
Authors: Gao Yue , Yan Xiaolu , Li Meng , Gao Han , Sun Jing , Zhu Shuyun , Han Shuang , Jia Li-Na , Zhao Xian-En , Wang Hua
Published: January 2018

For the first time, a FRET nanosensor for AA was developed using GQDs as the energy donors and SQA-iron(iii) as the energy acceptors.
CoC2O4·2H2O derived Co3O4nanorods array: a high-efficiency 1D electrocatalyst for alkaline oxygen evolution reaction
Authors: Wei Yicheng , Ren Xiang , Ma Hongmin , Sun Xu , Zhang Yong , Kuang Xuan , Yan Tao , Ju Huangxian , Wu Dan , Wei Qin
Published: January 2018

Self-standing Co3O4nanorods array on Co foil as a 1D OER catalyst electrode, only needs overpotential of 308 mV to drive 15 mA cm−2in 1.0 M KOH, with good long-term electrochemical durability and a high turnover frequency.
Growth of an 8-hydroxyquinoline single crystal by a modified Czochralski growth technique, and crystal characterization
Authors: Kumar Sonu , Kumar Binay
Published: January 2018

Piezoelectric 8-hydroxyqunoline crystal was grown by modified Czochralski set-up, designed for low melting point organic compounds. Hirshfeld surface and fingerprint plots were generated.
Molecular tectonics: high dimensional coordination networks based on methylenecarboxylate-appended tetramercaptothiacalix[4]arene in the 1,3-alternate conformation
Authors: Ovsyannikov A. S. , Ferlay S. , Solovieva S. E. , Antipin I. S. , Konovalov A. I. , Kyritsakas N. , Hosseini M. W.
Published: January 2018

Tetrasubstituted methylenecarboxylic-appended tetra-mercaptotetrathiacalix[4]arene (TMTCA), combined with transition metals, lead to high-dimensional coordination polymers.
Bulk and surface properties of the Ruddlesden–Popper oxynitride Sr2TaO3N
Authors: Bouri Maria , Aschauer Ulrich
Published: January 2018

Sr2TaO3N(001) surface states lead to spatial electron–hole separation, rationalising the good photocatalytic activity of this Ruddlesden–Popper oxynitride.
Catalytic nucleophilic ‘umpoled’ π-allyl reagents
Authors: Spielmann Kim , Niel Gilles , de Figueiredo Renata Marcia , Campagne Jean-Marc
Published: January 2018

This review highlights recent catalytic methods of reversal reactivity of classical π-allyl intermediates (nucleophile vs. electrophile) affording alternative and powerful ways for the allylation of carbonyl derivatives.
Achieving selectivity for copper over zinc with luminescent terbium probes bearing phenanthridine antennas
Authors: Harris S. M. , Srivastava K. , League A. B. , Ziebarth K. E. , Pierre V. C.
Published: January 2018

Terbium-based luminescent probes bearing either one, two, or three phenanthridine antennas respond selectively to CuI/II over ZnII.
Mechanistic insights into the tropo-inversion of the biphenyl moiety in chiral bis-amido phosphites and in their palladium(ii) complexes
Authors: Passera Alessandro , Iuliano Anna , Pérez-Torrente Jesús J. , Passarelli Vincenzo
Published: January 2018

The tropo-inversion of the biphenyl moiety in chiral bis-amido phosphites and in their palladium complexes has been elucidated by means of variable temperature NMR spectroscopy and DFT calculations.
Direct photoactivation of a nickel-based, water-reduction photocathode by a highly conjugated supramolecular chromophore
Authors: Shan Bing , Nayak Animesh , N. Sampaio Renato , Eberhart Michael S. , Troian-Gautier Ludovic , Brennaman M. Kyle , Meyer Gerald J. , Meyer Thomas J.
Published: January 2018

Control of photoinduced electron transfer flow in a NiO/dye/NiSx:Mo photocathode by a highly conjugated supramolecular chromophore for light-driven water reduction.
Aqueous production of spherical Zr-MOF beads via continuous-flow spray-drying
Authors: Avci-Camur Ceren , Troyano Javier , Pérez-Carvajal Javier , Legrand Alexandre , Farrusseng David , Imaz Inhar , Maspoch Daniel
Published: January 2018

Water is used in the spray-drying technique to synthesise microsized spherical beads of two Zr-MOFs.
Ruthenium–arene complexes with NSAIDs: synthesis, characterization and bioactivity
Authors: Tadić Ana , Poljarević Jelena , Krstić Milena , Kajzerberger Marijana , Aranđelović Sandra , Radulović Siniša , Kakoulidou Chrisoula , Papadopoulos Athanasios N. , Psomas George , Grgurić-Šipka Sanja
Published: January 2018

Two non-steroidal antiinflammatory drugs indomethacin and mefenamic acid were coordinated to Ru(ii)–arenes to afford four new complexes.
Hydrogen evolution reactions boosted by bridge bonds between electrocatalysts and electrodes
Authors: Liu Guanglei , Wang Zhanyu , Zu Lianhai , Zhang Yan , Feng Yutong , Yang Shihe , Jia Yu , Wang Songyou , Zhang Chi , Yang Jinhu
Published: January 2018

Interfacial bridge bonds (Ti–S–Co) have been found and proposed, which can strengthen the electrode–electrocatalyst integrity and boost the HER.
Operator‐based robust non‐linear vibration control for an L‐shaped arm with unknown load by using on‐line wavelet transform
Authors: Wu Yanfeng , Deng Mingcong
Published: January 2018

An L‐shaped arm with unknown load driven by a linear pulse motor is studied in this work. To control the motor motion and the arm vibration, an operator‐based non‐linear control is designed using an on‐line discrete wavelet transform (DWT). First, the dynamics of the L‐shaped arm vibration is modelled by considering the arm as a two‐dimensional Euler–Bernoulli beam. The relationship between the load and the arm vibration is given. Second, by using the on‐line DWT in the operator‐based non‐linear control, the proposed control for the system is designed. The wavelet transform is used to estimate the load and remove the influence of some undesired uncertainties. The operator‐based right coprime factorisation method is used to guarantee the robust stability of the motor‐arm system. The piezoelectric actuator is utilised to further reduce the arm vibration. The hysteresis of the piezoelectric actuator is compensated by using a Prandtl–Ishlinskii hysteresis model. Finally, simulation results are demonstrated to validate the proposed control.
New adaptive and centralised under‐voltage load shedding to prevent short‐term voltage instability
Authors: Modarresi Javad , Gholipour Eskandar , Khodabakhshian Amin
Published: January 2018

This study proposes a new adaptive and centralised under‐voltage load shedding (UVLS) to prevent short‐term voltage instability; it then examines the challenges related to the centralised UVLS. The proposed method uses a local measurement to estimate the amount of load shedding. It decreases the amount of load shedding by selecting the proper location of UVLS and shedding more powers within seconds after activating UVLS. Dynamic simulations are performed on the IEEE 118‐bus test system, New England test system, and on Isfahan regional power grid (IRPG) as the case studies. Simulation results, when compared with the conventional multi‐port network model and sensitivity‐based methods, provide a considerable reduction in the active power shedding in addition to the number of the load shedding steps. Moreover, it indicates that the measurement bias errors have a considerable effect on UVLS. Finally, a method is introduced to overcome the effect of measurement errors.
Frequency‐selective polarisation antenna based on simple rotational symmetric printed bow‐tie dipole structure
Authors: Xu Rui , Li Jian‐Ying , Liu Jie
Published: January 2018

In this study, a simple antenna with rotational symmetric bow‐tie dipole structure is proposed. The polarization of this antenna varied with the frequency, and is named frequency‐selective polarization antenna (FSPA). It is evolved from a basic bow‐tie dipole structure. After symmetrically cutting off two ellipses and rotational symmetrically incising two wide slits on the two arms of the bow‐tie dipole, FSPA is achieved. The lower linearly polarized (LP) and circularly polarized (CP) waves are produced by the larger tip. In the same way, the upper LP and CP waves are generated by the smaller tip. It can not only generate right‐hand circular polarization and left‐hand circular polarization with center frequencies of 2.40 and 5.30 GHz, but also radiate different LP waves as a dipole at two different bands. This antenna can get an impedance bandwidth (S11<−10 dB) of 98.7% from 1.9 to 5.65 GHz, the 3 dB axial ratio bandwidths can reach 8.3% (2.3–2.5 GHz) and 13.3% (4.9–5.6 GHz). The antenna peak gains at CP bands are 2.1 and 4.4 dBic, respectively. The peak gains at LP bands are 2.4 and 3.0 dBi, respectively. Furthermore, the radiation patterns perform well within these frequency bands.
Investigation of Plasma Formation with ns Laser by Using Focused Sub-ns Laser Probe
Authors: Ikeda Shunsuke , Kanesue Takeshi , Okamura Masahiro
Published: January 2018

A laser ablation plasma formation process was investigated by shooting another laser beam. The initial plasma was created by a mildly focused nanosecond laser beam and the probe laser, which has about ten times shorter pulse length with tightly focussed condition, was irradiated on it. By analysing high temperature plasma created by the probe laser, we could detect an interaction between the initial low temperature plasma and the probe laser. The interaction caused that the velocity of high temperature plasma generated by the sub-ns laser became smaller and the amount of the highly charged ions decreased. We found that the interaction does not occur during the irradiation of the first half of the ns laser. This fact indicates that the plasma is not produced during the first half of the ns laser.
Multi probes measurements at the PALS Facility Research Centre during high intense laser pulse interactions with various target materials
Authors: De Marco Massimo , Krása Josef , Cikhardt Jakub , Consoli Fabrizio , De Angelis Riccardo , Pfeifer Miroslav , Krůs Miroslav , Dostál Jan , Margarone Daniele , Picciotto Antonino , Velyhan Andriy , Klír Daniel , Dudžák Roman , Limpouch Jiří , Korn Georg
Published: January 2018

During the interaction of high intense laser pulse with solid target, a large amount of hot electrons is produced and a giant Electromagnetic Pulse (EMP) is generated due to the current flowing into the system target–target holder, as well as due to the escaping charged particles in vacuum. EMP production for different target materials is investigated inside and outside the target chamber, using monopole antenna, super wide-band microstrip antenna and Moebius antenna. The EMP consists in a fast transient magnetic field lasting hundreds of nanosecond with frequencies ranging from MHz to tens of GHz. Measurements of magnetic field and return target current in the range of kA were carried out by an inductive target probe (Cikhardt J. et al. Rev. Sci. Instrum. 85 (2014) 103507).
Tunneling decay of self-gravitating vortices
Authors: Dupuis Éric , Gobeil Yan , Lee Bum-Hoon , Lee Wonwoo , MacKenzie Richard , Paranjape Manu B. , Yajnik Urjit A. , Yeom Dong-han
Published: January 2018

We investigate tunneling decay of false vortices in the presence of gravity, in which vortices are trapped in the false vacuum of a theory of scalar electrodynamics in three dimensions. The core of the vortex contains magnetic flux in the true vacuum, while outside the vortex is the appropriate topologically nontrivial false vacuum. We numerically obtain vortex solutions which are classically stable; however, they could decay via tunneling. To show this phenomenon, we construct the proper junction conditions in curved spacetime. We find that the tunneling exponent for the vortices is half that for Coleman-de Luccia bubbles and discuss possible future applications.
Role of strangeness to the neutron star mass and cooling
Authors: Lee Chang-Hwan , Lim Yeunhwan , Hyun Chang Ho , Kwak Kyujin
Published: January 2018

Neutron star provides unique environments for the investigation of the physics of extreme dense matter beyond normal nuclear saturation density. In such high density environments, hadrons with strange quarks are expected to play very important role in stabilizing the system. Kaons and hyperons are the lowest mass states with strangeness among meson and bayron families, respectively. In this work, we investigate the role of kaons and hyperons to the neutron star mass, and discuss their role in the neutron star cooling.
A model for high-energy emission of the Intrabinary shock in pulsar binaries
Authors: An Hongjun
Published: January 2018

We present our studies of intrabinary shock emission for astrophysical binary systems with a neutron star. We construct a model for the shock emission and compare the model calculation with the light curve and the spectral energy distribution of the gamma-ray binary 1FGL J1018.6-5856. The model assumes a slow and a fast population of particles accelerated in the shock, and computes the high-energy emission spectra and orbital light curves produced by synchrotron, self-Compton and external Compton processes of the high-energy particles in the shock. The model allows one to study plasma properties and to constrain the binary geometry, most importantly the inclination angle (i). We discuss potential use of this model for other pulsar binaries to determine the inclination angle of the binary hence the mass of the neutron star.
On the analysis of the limited resources queuing system under MAP arrivals
Authors: Sopin Eduard , Samouylov Konstantin
Published: January 2018

In the paper, we analyse a multiserver queuing system with discrete limited resources and random resource requirements under MAP arrivals, which can adequately model resource allocation schemes in the contemporary wireless networks. The equilibrium system of equations is derived in the vector form and is solved numerically. With stationary probability distribution, we provide formulas for the average and the variance of the occupied resources, as well as for the blocking probability. The results are illustrated by a numerical example.
Influence of slope and external temperature on smoke stratification in case of fire in bi-directional road tunnel
Authors: Weisenpacher Peter , Glasa Jan , Valasek Lukas
Published: January 2018

Jet fan ventilation strategy in case of fire in bi-directional road tunnels is focused on maintaining smoke stratification. There are several factors influencing stratification under specific conditions. In this paper smoke movement during a 5 MW fire in a 600 m long road tunnel is studied by computer simulation and the influence of slope and external temperature on smoke stratification is analysed. Calculations were performed on a high performance computer cluster using parallel version of Fire Dynamics Simulator. Smoke stratification upstream of the fire is maintained in every simulation scenario with the exception of declivous tunnel, in which buoyancy intensifies backlayering. The behaviour of the smoke movement downstream of the fire is more complex. In the case of horizontal tunnel the stratification is not maintained in the vicinity of the fire and region with untenable conditions expands downstream. In the tunnel with slope of -2° this expansion is accelerated, while in the tunnel with slope of 2° untenable conditions spread in opposite direction. The influence of exterior temperature higher than temperature inside the tunnel is relatively weak in horizontal tunnels; however, it becomes very important in sloping tunnels, especially downstream of the fire.
Technological Forms Develope in Different Morphological Fields
Authors: Garleanu Delia , Arsene Delicia , Garleanu Gabriel , Borda Claudia
Published: January 2018

The present work is takes in consideration the experimental study of the influence of some morphological fields regarding the development of the complex technological forms. The goal that we have set in this paper was to bring in new points of view on technology morphologies arising in technological processes, whose goal is to generate surfaces.The development of the technological shapes could be controlled and oriented from the quality and quantity point of view, by using the morphological fields.. We refer here in particular to complex forms, not the Euclidean upon which adequate studies have been done already. Among the illustrations of the experimental parameters of forming events, electrochemical deposit is regarded as a paradigm for theoretical studies of diffusion limited aggregation. In fact, by changing the concentration of metal ions, the cathodic potential and the morphological field you can explore different morphologies, such as: dense radial aggregates, dendridic patterns and fractal aggregates. This topic has been treated and shown in the paper. The box-counting algorithm was used in calculating the fractal dimension of the deposited agregates.
Douleur dans les traitements orthodontiques par aligneurs thermoformés
Authors: Allereau Béatrice , Sabouni Waddah
Published: January 2018

Introduction : L'objectif de cette étude est d'évaluer la douleur générée au cours des traitements orthodontiques par aligneurs en termes d'intensité, de durée et de la caractériser. Matériels et méthodes : L'échantillon a regroupé 106 patients. La douleur a été étudiée selon son intensité et ses caractéristiques à partir du questionnaire de la Douleur de Saint Antoine. Pour l'analyse statistique, des tests de Student ont été réalisés. Résultats : 84 % des patients ressentent une douleur faible à modérée, avec une intensité significativement plus élevée chez les femmes. 31 % des patients ont consommé des antalgiques, sans corrélation établie entre le niveau d'intensité de la douleur et la prise d'antalgique. Pour 53 % des patients, la durée de la douleur était ≤ 2 jours ; pour 15 % des patients, elle a duré 7 jours. Chez les patients d'âge ≥ 40 ans, la durée de la douleur était significativement moindre que chez les patients d'âge < 40 ans. Dix qualificatifs de la douleur ont été retenus car décrits chez au moins un tiers des patients. Conclusion : Les traitements par gouttières provoquent une douleur faible à modérée, qui dure généralement 2 à 3 jours, mais peut durer 7 jours. Cette douleur est décrite comme une sensation de « compression », « élancement », « serrement », « tiraillement », « étirement », « coupure », et peut être « fatigante », « gênante », « désagréable », voire « pénible ».
Regioselective Late-Stage C-3 Functionalization of Pyrazolo[3,4-b]pyridines
Authors: Popowycz Florence , Lavrard Hubert
Published: January 2018

This contribution reports for the first time the late-stage C–H activation of pyrazolo[3,4-b]pyridine derivatives. A family of 16 molecules functionalized on the C-3 position by this methodology is demonstrated. After a careful optimization, a reliable procedure has been developed with Pd(phen)2(PF6)2 catalyst (10 mol%), affording C-3 arylated pyrazolo[3,4-b]pyridines in yields ranging from 40 to 81%.
Synthesis of Monofluoroalkenes: A Leap Forward
Authors: Paquin Jean-François , Drouin Myriam , Hamel Jean-Denys
Published: January 2018

Monofluoroalkenes have found wide application in organic chemistry, medicinal chemistry, and materials science. This review summarizes the most recent advances made regarding the preparation of monofluoroalkenes, covering the period between October 2010 and September 2017. This review is divided in three main parts, one for each possible substitution pattern, namely di-, tri-, and tetrasubstituted. Then, for each class, further subclassification is made according to the reaction type.

1 Introduction

2 Disubstituted Monofluoroalkenes

2.1 Disubstituted α-Monofluoroalkenes

2.2 Disubstituted β-Monofluoroalkenes

3 Trisubstituted Monofluoroalkenes

4 Tetrasubstituted Monofluoroalkenes

5 Conclusions
A Convenient Synthetic Approach to Saccharin Derivatives ­Containing a Sulfonylamidine Scaffold
Authors: Chen Yantao , Aurell Carl-Johan , Korsgren Pernilla , Malm Johanna , Härslätt Malin , Fridén-Saxin Maria , Pettersen Anna
Published: January 2018

A key intermediate was obtained as solid through filtration of the reaction mixture of saccharin, chloro(triphenyl)phosphonium chloride, and N,N-diisopropylethylamine (DIPEA) in chloroform. The soluble triphenylphosphine oxide went to filtrate as waste, while the solid was reacted with amines to afford N-sulfonylamidines. In total, 26 N-sulfonylamidine products were obtained in moderate to good overall yields.
Nasoseptal Flap for Skull Base Reconstruction in Children
Authors: Ben-Ari Oded , Wengier Anat , Ringel Barak , Carmel Neiderman Narin , Ram Zvi , Margalit Nevo , Fliss Dan , Abergel Avraham
Published: January 2018

Objective The endoscopic endonasal approach is being increasingly used for the resection and reconstruction of anterior skull base (ASB) lesions. Vascularized nasoseptal flaps (NSF) have become the workhorse for the reconstruction of ASB defects, resulting in a significant decrease in the incidence of cerebrospinal fluid (CSF) leaks. The objective of this study was to investigate the efficacy and safety of NSF in children.

Methods This is a retrospective analysis of the medical records of all patients under the age of 18 years who underwent endoscopic repair of ASB lesions with the use of NSF at our tertiary medical center between 1/2011 and 8/2016.

Results Twelve children underwent ASB defect repair for both benign and malignant neoplasms using the endoscopic endonasal NSF technique. Four children had previously undergone ASB surgery. The male-to-female ratio was 1:1, the average age was 12.3 years, the average hospitalization time was 8.3 days, and the maximum follow-up period was 24 months, during which craniofacial growth appeared to be unimpaired. A lumbar drain was used postoperatively in six cases. Crust formation and synechia were observed in two cases. There was one case of a major long-term complication (a CSF leak followed by meningitis).

Conclusions Endoscopic endonasal NSF was both an effective and a safe technique for ASB defect reconstruction in 12 children for both benign and malignant neoplasms. It had a high success rate and a low complication rate. No apparent negative influence on craniofacial growth was observed in our series.
Contralateral Minimum Anterior and Posterior Combined Petrosal Approach for Retrochiasmatic Craniopharyngiomas: An Alternative Technique
Authors: Goudihalli Sachin , Morisako Hiroki , Prastarana Wimba , Goto Takeo , Ohata Hiroki , Ohata Kenji
Published: January 2018

Retrochiasmatic craniopharyngiomas (RC) are a challenge for the neurosurgeon to treat surgically, restrained by their location in the interpeduncular fossa, surrounded by vital neurovascular structures, narrow corridor and poor visibility. Many approaches are possible and elucidated in the literature, which the surgeon chooses, based on multiple factors, such as the size of tumor, calcification, laterality, preoperative neurological deficits and the endocrine function status, recurrence, postradiotherapy status, or significant superior and/or posterior extension.1
2

We describe a contralateral minimum anterior and posterior (CL-MAPC) petrosal approach for a case of recurrent RC, in a 37-year-old female patient operated before using a pterional approach, now presented with left homonymous hemianopia and panhypopituitarism (Fig. 1). We preferred a contralateral approach to protect the ipsilateral optic tract (OT) from retraction injury, which formed an obstacle to the tumor from ipsilateral side. Apart from various benefits described by the author previously for RC, using MAPC petrosal approach, the CL-MAPC offers a safe corridor, protecting the ipsilateral OT, visualization of tumor origin usually posterior to chiasm, wider corridor if PCoM could be sacrificed, as it was done in this case, and pituitary stalk identification, with a probability of its functional preservation, unlike a necessity of pituitary transposition in EEA, though the endocrine outcome is poor after a radical resection irrespective of the approach chosen.1
3
4 There was complete excision of the tumor with preservation of visual function postoperatively. We recommend the use of CL-MAPC as an alternative to EEA in some specific indications when the tumor is large, calcified, obscuring OT on the ipsilateral side and with significant lateral extension, which may be limiting factors in EEA (Fig. 2).

The link to the video can be found at: https://youtu.be/gWCJmh4_evs.
Spinal cord schistosomiasis: Case report
Authors: Leitão Flávio , Figueiredo Djacir , Figueiredo Daniel , Bezerra de Menezes Dalgimar , Filho Flávio Leitão , Mattos João Paulo
Published: January 2018

The authors present a case of spinal cord schistosomiasis which simulated a tumoral lesion determining spastic paraparesis with a sensitive-motor level at T1. The patient was treated with surgery, praziquantel and dexamethasone, with “restitutio ad integrum”. Seven years later the patient presented recrudescence of the symptoms, without a good response to the medication and without a plausible explanation.

The authors wonder about the reasons of the low incidence of central nervous system schistosomosis in an endemic area such as the Northeast of Brazil. A brief review of the literature is done.
Risco de contágio ocupacional pelo sangue do doente durante os procedimentos neurocirúrgicos
Authors: Lemes de Oliveira Flávia Elisa Antunes , Akamoto Sato Claudia Reiko , Shibata Milton K.
Published: January 2018

A exposição ocupacional dos profissionais da área de saúde às doenças transmitidas pelo sangue tem sido preocupação crescente. Este estudo prospectivo foi realizado com o objetivo de avaliar a freqüência com que os profissionais que atuam na sala de operações neurocirúrgicas possam ser potencialmente contaminados através de contato direto com o sangue do doente. A ocorrência do contato dos profissionais com o sangue do doente, em 62 operações consecutivas, foi anotada em protocolo pré-estabelecido pela enfermeira da neurocirurgia do centro cirúrgico. O cirurgião foi o elemento da equipe cujo contato evidente com o sangue (através de ferimento perfurocortante ou através de contato cutâneo-mucoso sem ferimento) ocorreu com maior freqüência. Nesse profissional, contatos evidentes ocorreram, pelo menos uma vez, em 19,3% das operações realizadas, um terço deles por meio de ferimentos perfurocortantes. Seguiram-no, em ordem decrescente, a instrumentadora (9,7%) e a enfermeira (6,4%). Nenhum profissional que atua na sala de operações esteve livre do risco.

Este estudo demonstrou que a incidência, no cirurgião e na instrumentadora, de pelo menos um episódio de contato direto com o sangue, ou com outro material orgânico contaminado pelo sangue do doente, é elevada. Há, portanto, a necessidade de se dispor de protocolos escritos para notificação imediata das exposições ocupacionais aos patógenos transmitidos pelo sangue do doente. A notificação é importante para que o Serviço de Controle da Infecção Hospitalar da instituição analise os riscos de contágio e, se necessário, institua a profilaxia recomendada. É importante, também, que se adotem medidas, naquele ambiente, visando à prevenção de novos acidentes.
Hematoma extradural no idoso
Authors: Pereira Carlos Umberto , Silva Alvino Dutra da , Carneiro Leão João Domingos Barbosa , Machado Juliana de Carvalho , Machado Suzana de Carvalho , Alves Carvalho Portugal Maria da Glória
Published: January 2018

O hematoma extradural tem sido cada vez mais freqüente no idoso. Nessa faixa etária, a queda da própria altura é a principal causa. A tomografia computadorizada é o principal meio de diagnóstico. O prognóstico encontrase diretamente relacionado ao escore na escala de coma de Glasgow à admissão e à presença de lesões intracranianas associadas.
Prosopagnosia após ferimento por arma de fogo: Relato de caso
Authors: Almeida Leme Ricardo José de , Seng Shu Edson Bor , Sperling Cescato Valter Ângelo , Machado José Jorge , Sarkis Paulo Sérgio , Lefevre Beatriz
Published: January 2018

Relata-se o caso de uma jovem, vítima de estupro, seguido de ferimento na região occipital do crânio por arma de fogo. Após procedimento de limpeza cirúrgica e recuperação clínica pós-operatória, constatou-se que a paciente estava com quadro de prosopagnosia, com dificuldade no reconhecimento até mesmo de seus familiares, chegando a fazê-lo baseado em outros comemorativos como a voz e a forma de se vestir. A literatura foi revista, ressaltando-se alguns aspectos principais do quadro prosopagnósico.
Subluxação atlanto-axial traumática: Fixação com parafuso transarticular unilateral. Relato de caso
Authors: Botelho Ricardo Vieira , Ribeiro José Antônio , França Fontoura Emilio Afonso
Published: January 2018

É descrito o tratamento de uma paciente de 28 anos, que apresentava fratura vertebral cervical em dois níveis (fratura explosão de C6 e subluxação rotatória C1-C2). A massa lateral direita e a lâmina de C1 apresentavam-se fraturadas. Havia sido feita a traqueostomia precoce durante a admissão pelo grupo de emergência, o que dificultou o acesso pela via anterior. Foram realizadas a estabilização posterior C4-T1, com fixação segmentar (para estabilizar a lesão de C6) e a artrodese C1-C2 com o parafuso transarticular, apenas em uma articulação, devido a fraturas na articulação C1-C2 contralateral. O objetivo foi o de estabilizar a coluna espinhal, para movimentação e cuidados respiratórios, e preservar a motilidade occipto-C1,C2-C3 e C3-C4.

O controle, após 9 meses, mostrou estabilidade atlanto-axial mantida, com fusão interarticular, comprovando que, neste caso, a técnica transarticular unilateral foi suficiente para a fixação interna.
Diretrizes do atendimento ao paciente com traumatismo cranioencefálico
Authors: Andrade Almir Ferreira de , Ciquini Orildo , Figueiredo Eberval Gadelha , Brock Roger Schmidt , Marino Raul
Published: January 2018

A Sociedade Brasileira de Neurocirurgia, pelo Departamento de Trauma, com a Divisão de Clínica Neurocirúrgica da Faculdade de Medicina da Universidade de São Paulo e da Equipe Médica de Emergência do Pronto-Socorro de Neurocirurgia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, elaborou as Diretrizes do Atendimento ao Paciente com Traumatismo Cranioencefálico, buscando a homogeneidade de condutas e a redução dos índices de mortalidade e morbidade em todo país. Essas diretrizes possuem uma versão dedicada ao Atendimento Pré-hospitalar (Unidades de Resgate) e ao Atendimento Hospitalar imediato na Sala de Emergência. Com essa uniformização proposta, os estudos epidemiológicos poderão ser realizados de forma mais ampla e com dados mais seguros, permitindo identificar os pontos fracos e atuar com objetivos específicos, visando diminuir a morbidade e a mortalidade do paciente com traumatismo cranioencefálico.
Doppler intra-operatório na cirurgia dos aneurismas cerebrais
Authors: Figueirêdo Daniel Freire de , Figueirêdo Djacir Gurgel de , de Carvalho Francisco Flávio Leitão , Carvalho Filho Francisco Flávio Leitão de , Mendonça Caio , Mattos João Paulo
Published: January 2018

Os autores apresentam a experiência com o uso do doppler como auxiliar na cirurgia dos aneurismas cerebrais. O método foi usado em 58 pacientes com aneurismas intracranianos, distribuídos da seguinte maneira: 18 aneurismas do complexo comunicante anterior, 14 da artéria cerebral média e 28 da artéria carótida interna (supra e infraclinóidea). Dois pacientes tinham aneurismas múltiplos.

O protocolo utilizado consistiu em testar a patência dos vasos relacionados diretamente com o aneurisma, antes e após a clipagem do mesmo, e testar a total exclusão do aneurisma após a clipagem.

Os autores concluem que o método é extremamente seguro, instantâneo, efetivo, confiável, correlacionando com os resultados angiográficos, reduzindo o tempo e custo do tratamento, diminuindo a necessidade e os riscos da angiografia de controle pós-operatório.
Lesões medulares traumáticas agudas sem alterações radiológicas relacionadas com o trauma
Authors: Barros Leal Francisco Sérgio C. , Guimarães Antônio Celso A. , Franco Roberto R. , Veiga José Carlos E.
Published: January 2018

As lesões medulares traumáticas sem alterações radiológicas relacionadas com o trauma, como o próprio nome sugere, constituem uma entidade na qual há sinais clínicos de lesão medular na ausência de anomalias radiológicas próprias do traumatismo (radiografia simples e tomografia computadorizada). Contudo, podem estar associadas a outras alterações (espondilose, canal estreito, espondilite anquilosante, hérnias de disco, etc.). Caso a ressonância magnética fosse incluída na investigação, haveria uma redução significativa na incidência dessas lesões e dificilmente deixariam de ser diagnosticadas. Foram estudados 14 pacientes com idades entre 21 e 70 anos admitidos em nosso serviço, no período de 1989 a 1997, submetidos a estudo radiográfico simples (incluindo estudo dinâmico) e/ou tomografia computadorizada da coluna vertebral cervical. Em todos os casos, foram descartadas alterações radiológicas relacionadas com o trauma.

O sexo masculino predominou (13 casos) e houve uma preponderância do grupo etário entre a quinta e sétima décadas (11 casos). Todos tinham disfunções referentes à medula cervical, em algum momento: dois apresentavam tetraparesia transitória (concussão medular), nove apresentavam síndrome centromedular, um tinha tetraparesia de predomínio crural e, dois, tetraplegia flácida. O mecanismo do trauma foi hiperextensão cervical em 13 pacientes. Espondilose cervical foi observada em 13 casos. O diâmetro do canal cervical foi: inferior a 13 mm, em um paciente; entre 13 mm e 14 mm, em quatro; 15 mm e 16 mm, em três; 17 mm e 18 mm, em dois; e superior a 18 mm, em um. Hérnia de disco traumática ocorreu em um caso. Três doentes morreram.

Na nossa casuística, as lesões medulares traumáticas sem alterações radiológicas relacionadas com o trauma foram mais comuns em homens, com mais de 40 anos, com estreitamento do canal vertebral, submetidos à hiperextensão cervical aguda. O prognóstico parece estar relacionado com a gravidade do quadro clínico inicial e as alterações encontradas na ressonância magnética.

A terminologia “lesões medulares traumáticas sem alterações radiológicas relacionadas com o trauma” parece-nos inadequada e deve ser revista.
Metástase de meningeoma para linfonodos cervicais: Relato de caso e revisão da literatura
Authors: Souza Heider Lopes de , Caldas João Rabelo , Menguita Luiz Gonzaga , Gomes Pereira Hougelle Simplício , Souza Moura Jorge Alberto , Gurjão Madureira João Flávio , Lana Janaína Martins de
Published: January 2018

Os autores relatam um caso de meningeoma atípico da goteira olfatória, acometendo um paciente de 74 anos, do sexo masculino, apresentando-se com quadro de hipertensão intracraniana e confusão mental. Após exérese cirúrgica, houve recidiva local precoce e metástase ganglionar cervical. As metástases extracranianas de meningeomas intracranianos já foram bem documentadas, mas são raramente encontradas. Ocorre em menos de 0,1% desses tumores. Os locais mais comuns dessas metástases são os pulmões (60%), o fígado (34%), os linfonodos cervicais (18%), os ossos longos, a pélvis e o crânio (11%).
O nascimento da neurocirurgia brasileira
Authors: Gusmão Sebastião Silva , Souza José Gilberto de
Published: January 2018

Relata-se a vida profissional dos precursores e pioneiros que possibilitaram o nascimento da neurocirurgia brasileira e a fundação da Sociedade Brasileira de Neurocirurgia.
Aneurismas paraclinóides: Experiência com 25 casos
Authors: Ramos Francisco F. , Ferreira Arnaldo , de Sá Filho Raimundo N. , Marques Marcos Alcino S. S. , Cardoso Arquimedes C. , Leal Filho Manoel Baldoino
Published: January 2018

Os autores apresentam experiência com 25 casos de aneurismas paraclinóides, tratados entre janeiro de 1995 e janeiro de 1998; fazem parte da casuística 270 aneurismas operados nesse período.

Utilizou-se a técnica divulgada por Dolenc, com exposição da artéria carótida cervical ipsilateral para todos os casos de aneurismas gigantes. A média de idade foi de 45 anos; 84% tiveram hemorragia subaracnóidea, 20%, algum déficit visual e 8%, amaurose. Com relação à escala de Hunt-Hess, 20% foram admitidos com escore IV ou V. A incidência de aneurismas múltiplos foi 36%, 24% foram considerados grandes e 40%, gigantes. Todos foram operados após a primeira semana e a grande maioria foi operada entre a segunda e a quarta semanas após o sangramento. Dos 25 casos operados, em 12% houve sangramento durante a microdissecção e, em outros 12%, utilizou-se a clipagem temporária programada.

O resultado do tratamento foi excelente em 40%, bom em 24%, 16% ficaram com déficit visual (adquirido no pré-operatório), em 16% houve seqüelas graves e houve um óbito, correspondendo à mortalidade de 4%. Na experiência dos autores, a exposição da artéria carótida na região cervical, para os aneurismas gigantes, a ressecção da apófise clinóide anterior e a exposição da artéria carótida distal ao aneurisma foram os pontos mais importantes na tática cirúrgica dos casos citados.
Metástase cerebral como manifestação inicial de adenocarcinoma de próstata: Relato de dois casos
Authors: Pereira Carlos Umberto , Costa Mônica Duarte , Carneiro Leão João Domingos Barbosa , Batista Soares Sérgio Agnaldo Monteiro
Published: January 2018

O acometimento do sistema nervoso central por neoplasia primária de próstata é raro. Cerca de 2% a 4% dos pacientes com adenocarcinoma de próstata disseminado apresentam metástases parenquimatosas para cérebro ou medula espinhal. A metástase cerebral por adenocarcinoma de próstata ocorre por disseminação hematogênica a distância, somente após comprometimento dos ossos e pulmões.

Os autores descrevem dois casos de metástases cerebrais como manifestação inicial de adenocarcinoma de próstata, sem acometimento clínico de outros órgãos. Discutem sua via de disseminação e prognóstico. Sem dúvida, pode haver lesão em outros órgãos que não se manifestaram clinicamente e apresentam um péssimo prognóstico.
Hérnia discal lombar alta em dois níveis: Relato de caso
Authors: de Almeida Leme Ricardo J. , Seng Shu Edson Bor , Taricco Mário A.
Published: January 2018

As hérnias lombares de disco da região de L1 até L3 correspondem a menos de 5% dos casos de todas as herniações discais. A maioria ocorre nos níveis L4-L5 e L5-S1. Os autores relatam o caso de uma paciente com dor lombar na região anterior da coxa esquerda, compatível com radiculopatia L2 e L3, cuja investigação mostrou hérnias discais L1-2 e L2-3, e discutem aspectos clínicos, terapêuticos e diagnósticos diferenciais.