检索结果-南通市图书馆

溶酶体酸化可增强吞噬性星形胶质细胞的消化功能

在线全文

学校读者我要写书评

暂无评论

神经损伤与功能重建 2015年第5期10卷 425-425页

作者： kelly r.monk M.Laura Feltri Carla Taveggia Camilla Lv Claire H.Mitchell Martin Simonsson Anna Erlandsson 唐颖馨 Department of Neuroscience Uppsala University Uppsala University Hospital Department of Anatomy and Cell Biology University of Pennsylvania Department of Physiology University of Pennsylvania SciL ife Lab and Department of Computer Science Electrical & Space Engineering Lulea University of Technology Department of Public Health and Caring Sciences Uppsala University Rudbeck Laboratory

低效的溶酶体降解是多种脑部疾病发展的中心环节,但其具体机制及参与的细胞种类仍不清楚。既往研究显示,星形胶质细胞大量吞噬死亡的细胞,但将这些吞噬的物质储存在细胞内而不是进行降解。本研究对星形胶质细胞降解消化功能减弱的原因... 详细信息

低效的溶酶体降解是多种脑部疾病发展的中心环节,但其具体机制及参与的细胞种类仍不清楚。既往研究显示,星形胶质细胞大量吞噬死亡的细胞,但将这些吞噬的物质储存在细胞内而不是进行降解。本研究对星形胶质细胞降解消化功能减弱的原因进行研究,并探索增强星形胶质细胞降解消化功能的方法。结果显示,长期存在于吞噬泡周围的肌动环阻碍了溶酶体的吞噬溶解作用。此外,rab27a蛋白可以通过Nox2减少溶酶体的酸化,而星形胶质细胞高表达rab27a蛋白,阻碍抗原呈递。本研究还发现,Nox2与星形胶质细胞摄取的物质共定位,且表达主要组织相容性复合体II,提示这可能影响星形胶质细胞内的抗原呈递。使用酸化纳米粒子对星形胶质细胞溶酶体进行长时间的酸化处理,能增加星形胶质细胞对所摄取物质和死亡细胞的消化。但随着酸化时间的延长,星形胶质细胞的消化能力再次回复到较低水平,提示随着酸化作用的增强,细胞的对抗酸化的通路也相应增强了。

关键词： Nox2 消化星形胶质细胞溶酶体纳米粒子 pHrodo 染料吞噬作用

Multilayer network analyses as a toolkit for measuring social structure

在线全文

学校读者我要写书评

暂无评论

Current Zoology 2021年第1期67卷 81-99页

作者： kelly r.FINN Neukom Institute Dartmouth CollegeHanoverNH 03755USA

The formalization of multilayer networks allows for new ways to measure sociality in complex social systems,including groups of *** same mathematical representation and methods are widely applicable across fields and study systems,and a network can represent drastically different types of *** such,in order to apply analyses and interpret the results in a meaningful way the researcher must have a deep understanding of what their network is representing and what parts of it are being measured by a given *** social networks can represent social structure with more detail than is often present in single layer networks,including multiple"types"of individuals,interactions,or relationships,and the extent to which these types are *** networks can also encompass a wider range of social scales,which can help overcome complications that are inherent to measuring *** this paper,I dissect multilayer networks into the parts that correspond to different components of social structures.I then discuss common pitfalls to avoid across different stages of multilayer network analyses-some novel and some that always exist in social network analysis but are magnified in multi-layer *** paper serves as a primer for building a customized toolkit of multilayer network analyses,to probe components of social structure in animal social systems.

关键词： animal behavior multilayer networks relationships sociality social networks social structure subgroups

Dentromere Size and Its relationship to Haploid Formation in Plants

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2018年第3期11卷 398-406页

作者： Na Wang r. kelly Dawe Department of Plant Biology University of Georgia Athens GA 30602 USA Department of Genetics University of Georgia Athens GA 30602 USA

Wide species crosses often result in uniparental genome elimination and visible failures in centromere func- tion. Crosses involving lines with mutated forms of the CENH3 histone variant that organizes the centromere/ kinetochore interface have been shown to have similar effects, inducing haploids at high frequencies. Here, we propose a simple centromere size model that endeavors to explain both observations. It is based on the idea of a quantitative centromere architecture where each centromere in an individual is the same size, and the average size is dictated by a natural equilibrium between bound and unbound CENH3 （and its chaperones or binding proteins）. While centromere size is determined by the cellular milieu, centromere positions are heritable and defined by the interactions of a small set of proteins that bind to both DNA and CENH3. Lines with defective or mutated CENH3 have a lower loading capacity and support smaller centromeres. In cases where a line with small or defective centromeres is crossed to a line with larger or normal centromeres, the smaller/defective centromeres are selectively degraded or not maintained, resulting in chromosome loss from the small-centromere parent. The model is testable and generalizable, and helps to explain the coun- terintuitive observation that inducer lines do not induce haploids when crossed to themselves.

关键词： chromosome loss genome elimination aneuploidy kinetochore CENH3 CENP-A

Coincidence Properties for Maps from the Torus to the Klein Bottle

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2008年第4期29卷 425-440页

作者： Daciberg L.GONCALVES Michael r.kelly Departamento de Matemática IME USP Department of Mathematics Loyola University

The authors study the coincidence theory for pairs of maps from the Torus to the Klein bottle. reidemeister classes and the Nielsen number are computed, and it is shown that any given pair of maps satisfies the Wecken property. The 1-parameter Wecken property is studied and a partial negative answer is derived. That is for all pairs of coincidence free maps a countable family of pairs of maps in the homotopy class is constructed such that no two members may be joined by a coincidence free homotopy.

关键词： Coincidence point Nielsen number Wecken property

Inhibiting the kynurenine pathway in spinal cord injury: multiple therapeutic potentials?

在线全文

学校读者我要写书评

暂无评论

Neural regeneration research 2018年第12期13卷 2073-2076页

作者： kelly r.Jacobs David B.Lovejoy Neuroinflammation Group Centre for Motor Neuron Disease Research Department of Biomedical Sciences Faculty of Medicine and Health Sciences Macquarie University

Chronic induction of the kynurenine pathway（KP） contributes to neuroinflammation by producing the excitotoxin quinolinic acid（QUIN）. This has led to significant interest in the development of inhibitors of this pathway, particularly in the context of neurodegenerative disease. However, acute spinal cord injury（SCI） also results in deleterious increases in QUIN, as secondary inflammatory processes mediated largely by infiltrating macrophages, become predominant. QUIN mediates significant neurotoxicity primarily by excitotoxic stimulation of the N-methyl-D-aspartate receptor, but other mechanisms of QUIN toxicity are known. More recent focus has assessed the contribution that neuroinflammation and modulations in the KP make in mood and psychiatric disorders with recent studies linking inflammation and modulations in the KP, to impaired cognitive performance and depressed mood in SCI patients. We hypothesize that these findings suggest that in SCI, inhibition of QUIN production and other metabolites, may have multiple therapeutic modalities and further studies investigating this are warranted. However, for central nervous system-based conditions, achieving good blood-brain-barrier permeability continues to be a limitation of current KP inhibitors.

关键词： spinal cord injury neuroinflammation kynurenine pathway activated microglia infiltrating macrophages quinolinic acid neuropsychiatry depression

Low concentrations of atrazine,glyphosate,2,4-dichlorophenoxyacetic acid,and triadimefon exposures have diverse effects on Xenopus laevis organ morphogenesis

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2010年第9期22卷 1305-1308页

作者： Jenny r.Lenkowski Gabriela Sanchez-Bravo kelly A.McLaughlin Department of Biology Tufts University

Many chemicals are released into the environment, and chemical contamination has been suggested as a contributing factor to amphibian declines. To add to a growing body of knowledge about the impact of individual chemicals on non-target organisms, we examined the specificity of deformities induced by exposure to four pesticides （atrazine, 2,4-dichloropheoxyacetic acid （2,4-D）, triadimefon, and glyphosate） in the model amphibian species, Xenopus laevis. We focused on the period of organ morphogenesis, as it is frequently found to be particularly sensitive to chemical exposure yet also commonly overlooked. We found similar levels of intestine malformations and edemas, as well as disruption of skeletal muscle, in atrazine and triadimefon exposed tadpoles. The effects of 2,4-D were only apparent at the highest concentrations we examined; glyphosate did not induce dramatic malformations at the concentrations tested. While researchers have shown that it is important to understand how chemical mixtures affect non-target organisms, our results suggest that it is first crucial to determine how these chemicals act independently in order to be able to identify consequences of individual pesticide exposure.

关键词： amphibian pesticide organ morphogenesis teratogenesis toxicology Xenopus laevis

Hybridization despite elaborate courtship behavior and female choice in Neotropical tree frogs

在线全文

学校读者我要写书评

暂无评论

Integrative Zoology 2023年第2期18卷 208-224页

作者： renato C.NALI kelly r.ZAMUDIO Cynthia P.A.PrADO Programa de Pós-Graduação em Ecologia Evolução e BiodiversidadeInstituto de BiociênciasUniversidade Estadual PaulistaRio ClaroSão PauloBrazil Department of Ecology and Evolutionary Biology Cornell UniversityIthacaNew YorkUSA Department of Integrative Biology University of TexasAustinTexasUSA Departamento de Morfologia e Fisiologia Animal Faculdade de Ciências Agrárias e VeterináriasUniversidade Estadual Paulista“Júlio de Mesquita Filho”JaboticabalSão PauloBrazil

The mechanisms of hybridization can be elucidated by analyzing genotypes as well as phenotypes that could act as premating barriers,as the reproductive interactions among heterospeciﬁcs can alter the evolutionary history of *** frogs,hybrids typically occur among species that reproduce explosively(in dense aggregations)with few opportunities for mate selection but are rare in species with elaborate courtship behaviors that may prevent erroneous *** 21 microsatellite markers,we examined hybridization in the prolonged-breeding tree frogs Bokermannohyla ibitiguara and *** sampled within a contact zone in the Brazilian savanna(72 tadpoles;74 adults).We also compared acoustic and morphological *** conﬁrmed both parental species genetically;STrUCTUrE results conﬁrmed 14 hybrids,11 of which were second-generation according to NEWHYBrIDS,all with intermediate values of genetic dissimilarities compared to the *** and acoustic analyses revealed that hybrids showed variable but not necessarily intermediate ***,2 hybrids exhibited call types different from *** reproduction of *** involves territorial and aggressive males,elaborate courtships with acoustic and tactile stimuli,choosy females,and opportunistic *** study uncovers a rare case of viable hybridization among closely related frogs with such a combination of complex courtship behaviors and mate *** discuss the likely directionality and mechanisms behind this phenomenon,and highlight the importance of investigating hybridization even in species that show elaborate reproduction and female choice to advance our understanding of animal diversiﬁcation.

关键词： heterospeciﬁc mating hybrid zone Hylidae microsatellites prolonged-breeding

SnrK1a1, a new player in the sucrose-Opaque2 network during endosperm filling

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2024年第8期17卷 1172-1174页

作者： kelly Mayrink Balmant Marcio F.r.resende Jr. Horticultural Sciences Department University of FloridaGainesvilleFLUSA

Maize(Zea mays)endosperm is an important food source for humans and *** addition,it is considered an excellent model for research on seed development because of its relatively large size for both embryo and endosperm compared to those of other crop species,such as rice(Oryza sativa)and wheat(Triticum aestivum).After double fertilization,early maize endosperm development includes three stages:(i)a multinucleate coenocyte stage;(i)a cellularization stage,in which the cellular endosperm is formed;and(ii)a stage of differentiation into distinct *** early differentiation,four major cell types with specific functions differentiate within the endosperm:starchy endosperm,aleurone layer,basal endosperm transfer layer(BETL),and embryo surrounding *** subaleurone,conducting zone,basal intermediate zone,and endosperm adjacent to scutellum arise in late differentiation(Sabelli and Larkins 2009).After the main cell types are established,maize endosperm undergoes intensive cell proliferation,which marks the transition to the endosperm-filling *** the endosperm-flling stage,the maternal sucrose products are transported to seeds through the BETL region,where they will act as the main carbon substrate for storage products such as starch and proteins(Chen et al.,2023).In fact,the endosperm of maize seeds accounts for approximately 90%of the total grain weight,serving as an important nutrient reservoir(Flint-Garcia et al.,2009).

关键词： endosperm reservoir Flint

Acute inflammatory demyelinating polyneuropathy associated with pegylated interferon α 2a therapy for chronic hepatitis C virus infection

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2008年第2期14卷 318-321页

作者： Vijay Khiani Thomas kelly Adeel Shibli Donald Jensen Smruti r Mohanty Department of Medicine Case Western Reserve University Cleveland OH United States Department of Neurology The University of ChicagoChicago IL United States Department of Medicine Weiss Memorial Hospital Chicago IL United States Department of Medicine Center for Liver Diseases The University of Chicago Chicago IL United States

The combination of pegylated interferon (Peg-IFN) and ribavirin is the standard of care for chronic hepatitis C virus (HCV) infection treatment. In general, common side effects related to this combination therapy are mild and are very well tolerated. However, peripheral neuropathy including demyelinating polyneuropathy related to Peg-IFN is extremely rare. We present the first case of an acute inflammatory demyelinating polyneuropathy (AIDP) associated with Peg-IFN-α 2a (Pegasys) after 16 wk of a combination therapy with Pegasys and ribavirin in a 65-year-old woman with chronic HCV infection. She developed tingling, numbness, and weakness of her upper and lower extremities and was hospitalized for acute neurological deficits. Her clinical course, neurological findings, an electromyogram (EMG), nerve conductions studies (NCS), muscle biopsy, and a sural nerve biopsy were all consistent with AIDP likely related to Pegasys use. The patient recovered completely with the use of intravenous immunoglobulin (IVIG) including physical therapy and neurological rehabilitation. It is very important that gastroenterologists and/or hepatologists recognize this rare neurological complication related to Peg-IFN treatment very early, since it requires a prompt discontinuation of therapy including an immediate referral to a neurologist for the confirmation of diagnosis, management, and the prevention of long-term neurological deficits.

关键词： Neuropathy Pegylated interferon Pegasys