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Expression of a fusion protein of human ciliary neurotrophic factor and soluble CNTF-Receptor and identification of its activity

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Journal of Zhejiang University Science 2003年第3期4卷 340-345页

作者：陈益 mārzPia OttenUwe 葛霁光 rose-JohnStefan CollegeofLifeSciences ZhejiangUniversityHangzhou310027China DepartmentofPhysiology BaselUniversityVesalgasse14051BaselSwitzerland DepartmentofBiochemistry Christian-AlbrechtsUniversityofKielD-24098KielGermany

Ciliary neurotrophic factor (CNTF) has pleiotropic actions on many neuronal populations as well as on glia. Signal transduction by CNTF requires that it bind first to CNTF R, permitting the recruitment of gp130 and LIF R, forming a tripartite receptor complex. Cells that only express gp130 and LIF R, but not CNTF R are refractory to stimulation by CNTF. On many target cells CNTF only acts in the presence of its specific agonistic soluble receptors. We engineered a soluble fusion protein by linking the COOH terminus of sCNTF R to the NH 2 terminus of CNTF. Recombinant CNTF/sCNTF R fusion protein (Hyper CNTF) was successfully expressed in COS 7 cells. The apparent molecular mass of the Hyper CNTF protein was estimated from western blots to be 75 kDa. Proliferation assays of transfected BAF/3 cells in response to CNTF and Hyper CNTF were used to verify the activity of the cytokines. The proliferative results confirmed that CNTF required homodimerization of the gp130, CNTF R and LIF R receptor subunit whereas Hyper CNTF required heterodimerization of the gp130 and LIF R receptor subunit. We concluded that the fusion protein Hyper CNTF had superagonistic activity on target cells expressing gp130 and LIF R, but lacking membrane bound CNTF R.

关键词： Ciliary neurotrophic factor(CNTF) Soluble CNTF Receptor Fusion protein Biological activity

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa m.G.Cassiano Roney S.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNS)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

Nest predators, nest-site selection and nest success of the Emei Shan Liocichla(Liocichla omeiensis), a vulnerable babbler endemic to southwestern China

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Chinese Birds 2016年第3期7卷 161-166页

作者： Yiqiang Fu Benping Chen Simon D.dowell Zhengwang Zhang Sichuan Institute Key Laboratory for Protecting Endangered Birds in the Southwest Mountains College of Life Sciences Leshan Normal University Laojunshan National Nature Reserve Administration North of England Zoological Society Chester Zoo ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life Sciences Beijing Normal University

Background: The Emei Shan Liocichla(Liocichla omeiensis) is a globally vulnerable babbler, endemic to southwestern China. We investigated its nest predators, nest-site selection and nest success at the Laojunshan National Nature Reserve in Sichuan, China in order to identify the precise nesting-habitat requirements of the species, and to test whether the nest-site-selection cues, preferred by the Emei Shan Liocichla, are positively associated with nest ***: We used infrared cameras to determine nest predators. We compared the microhabitat attributes between nest and random sites, as well as successful and failed nests. We used Binary Logistic Regression to determine the most important variables affecting nest-site selection of the Emei Shan Liocichla. We used the nest survival analysis in Program mARK to estimate daily nest survival rates(DSR). Nest success was calculated using the mayfield ***: In total 56 nests were found. The DSR for all nests that contained at least one egg was 0.9564 ± 0.0091(95 % CI 0.9346–0.9711)(n = 40), while the total nest success was 27.5 %. We identified four categories of predators in 10 nest predation events, i.e. squirrels(n = 5), snakes(n = 3), raptors(n = 1) and wasps(n = 1). We found that:(1) nest predation was the primary reason for nest failure of the Emei Shan Liocichla,(2) tree cover, bamboo cover, liana abundance and distance to forest edge or gap were the most important variables affecting nest-site selection of this species, and(3) the nest-site-selection variables we measured appeared not to be positively associated with nest ***: Our findings suggest that the Emei Shan Liocichla tended to select nest sites near forest edges or gaps with good concealment and that nest-site selection by this species was nonrandom but not necessarily adaptive. Reducing forest-edge development and protecting bamboo stands should be effective for conservation of this species.

关键词： Nest predator Nest-site selection Nest success Liocichla omeiensis Laojunshan Nature Reserve

Arctic sea-ice extent: No record minimum in 2023 or recent years

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola m.Johannessen Tor I.Olaussen Nansen Scientific Society BergenNorway Nansen Environmental and Remote Sensing Center BergenNorway

Arctic sea-ice extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. In general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic minimum ice Climate

Insights from an academic endeavor into central nervous system drug discovery

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Neural Regeneration Research 2025年第6期20卷 1717-1718页

作者： Lieve van Veggel An m.Voets Tim Vanmierlo Rudy Schreiber BIOmED Biomedical Research Institute Faculty of Medicine and Life SciencesHasselt UniversityHasseltBelgium Department of Psychiatry and Neuropsychology Division of Translational NeuroscienceEuropean Graduate School of NeuroscienceSchool for Mental Health and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands Section of Psychopharmacology Neuropsychology and PsychopharmacologyFaculty of Psychology and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands University mS Center(UmSC) Hasselt-PeltBelgium

Historically,"big pharma"did most central nervous system drug discovery R&D ***,in modern times their"management reductionism"resulted in disappointing pipelines and pharma resided to(late)development,regulatory approval,and marketing(Thong,2015).This had significant consequences for financing and executing research,resulting in a larger role for funding by governments and patient-organizations and a shift of research to academia(mazzucato,2013).

关键词： academic approval consequences

Neurocircuit regeneration by extracellular matrix reprogramming

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Neural Regeneration Research 2025年第8期20卷 2300-2301页

作者： Shengzhang Su Ian N.Levasseur Kimberly m.Alonge Department of medicinal Chemistry University of WashingtonSeattleWAUSA Department of Chemistry University of WashingtonSeattleWAUSA Department of medicine University of Washington Medicine Diabetes InstituteSeattleWAUSA

The brain's extracellular matrix(ECm),which is comprised of protein and glycosaminoglycan(GAG)scaffolds,constitutes 20%-40% of the human brain and is considered one of the largest influencers on brain cell functioning(Soles et al.,2023).Synthesized by neural and glial cells,the brain's ECm regulates a myriad of homeostatic cellular processes,including neuronal plasticity and firing(miyata et al.,2012),cation buffering(moraws ki et al.,2015),and glia-neuron interactions(Anderson et al.,2016).Considering the diversity of functions,dynamic remodeling of the brain's ECm indicates that this understudied medium is an active participant in both normal physiology and neurological diseases.

关键词： matrix programming

Transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 177-192页

作者： m.NAVEED m.ImRAN T.ASGHAR Z.ABBAS Department of mathematics Division of Science and TechnologyUniversity of Education Department of mathematics The Islamia University of Bahawalpur

This paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. The influence of magnetic fields is also inspected in terms of their physical characteristics. To depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAm).The effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

关键词： hybrid nanofluid oscillating curved stretchable sheet gyrotactic microorganism Cattaneo-Christov heat and mass flux chemical reaction analytical solution O368

Hopf-flip bifurcation of high dimensional maps and application to vibro-impact systems

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Acta mechanica Sinica 2005年第4期21卷 402-410页

作者： Jianhua Xie Wangcai Ding E.H. dowell L. N. Virgin Department of Applied mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China School of mechanical Engineering Lanzhou Jiaotong UniversityLanzhou 730070 China School of Engineering.Duke University. Durham NC27708-0300USA

This paper addresses the problem of Hopf-flip bifurcation of high dimensional maps. Using the center manifold theorem, we obtain a three dimensional reduced map through the projection technique. The reduced map is further transformed into its normal form whose coefficients are determined by that of the original system. The dynamics of the map near the Hopf-flip bifurcation point is approximated by a so called “time-2τ^2 map” of a planar autonomous differential equation. It is shown that high dimensional maps may result in cycles of period two, tori T^1 （Hopf invariant circles）, tori 2T^1 and tori 2T^2 depending both on how the critical eigenvalues pass the unit circle and on the signs of resonant terms＇ coefficients. A two-degree-of-freedom vibro-impact system is given as an example to show how the procedure of this paper works. It reveals that through Hopf-flip bifurcations, periodic motions may lead directly to different types of motion, such as subharmonic motions, quasi-periodic motions, motions on high dimensional tori and even to chaotic motions depending both on change in direction of the parameter vector and on the nonlinear terms of the first three orders.

关键词： maps Vibro-impact dynamics Hopf-flip bifurcation Torus Chaos

Improved tabledng behavior of paracetamol in the presence of polyvinylpyrrolidone additive: Effect of mixing conditions

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Particuology 2019年第2期17卷 9-18页

作者： Ayuk Agbor rose Waseem Kaialy School of Pharmacy Faculty of Science and Engineering University of Wolverhampton Wolverhampton WV1 1LY UK

monoclinic paracetamol (PA) is notorious as a poorly compactible model drug. Polyvinylpyrrolidone (PVP) is a polymer that can act as an effective binder to improve the mechanical properties of PA. It is surprising however that the role of mixing conditions on the physicochemical and mechanical properties of PA-PVP mixtures has not been reported previously. The results of this work showed that PA-PVP mixtures containing 5%(w/w) PVP prepared using high energy mixing conditions had considerably smaller particle size distributions and higher cohesivities than mixtures prepared using low energy mixing conditions. Solid-state analysis did not detect any change in the monoclinic crystalline form of PA after mixing with PVP. The following rank order of tabletability for PA-PVP mixtures was obtained according to the mixing condition: low shear-medium shearmogenization. A higher level of hydrogen bonding was detected in the mixtures prepared via high energy mixing conditions than in those prepared using low energy mixing conditions. mixing is therefore a critical process that needs to be optimized during the preparation of in teractive mixtures for tableting.

关键词： Direct compression Interactive mixtures Hydrogen bonding mechanical properties Physicochemical properties Tableting