Microscopy最新文献_第3页

Single-molecule Observation of Self-Propagating Amyloid Fibrils. 自繁殖淀粉样纤维的单分子观察。

IF 1.8 4区工程技术

Microscopy Pub Date : 2022-03-07 DOI: 10.1093/jmicro/dfac011

T. Watanabe-Nakayama, K. Ono

{"title":"Single-molecule Observation of Self-Propagating Amyloid Fibrils.","authors":"T. Watanabe-Nakayama, K. Ono","doi":"10.1093/jmicro/dfac011","DOIUrl":"https://doi.org/10.1093/jmicro/dfac011","url":null,"abstract":"The assembly of misfolded proteins into amyloid fibrils is associated with amyloidosis, including neurodegenerative diseases, such as Alzheimer's, Parkinson's, and prion diseases. The self-propagation of amyloid fibrils is widely observed in the aggregation pathways of numerous amyloidogenic proteins. This propensity with plasticity in primary nucleation allows amyloid fibril polymorphism, which is correlated with the pathology/phenotypes of patients. Because the interference with the nucleation and replication processes of amyloid fibrils can alter the amyloid structure and the outcome of the disease, these processes can be a target for developing clinical drugs. Single-molecule observation of amyloid fibril replication can be an experimental system to provide the kinetic parameters for simulation studies and confirm the effect of clinical drugs. Here, we review single-molecule observation of the amyloid fibril replication process using fluorescence microscopy and time-lapse atomic force microscopy, including high-speed atomic force microscopy. We discussed the amyloid fibril replication process and combined single-molecule observation results with molecular dynamics simulations. Mini Abstract Structural dynamics in amyloid aggregation is related with various Alzheimer's and Parkinson's disease symptoms. Single-molecule observation using high-speed atomic force microscopy can directly visualize the structural dynamics of individual amyloid aggregate assemblies. Here, we review historical and recent studies of single-molecule observation of amyloid aggregation with supportive molecular dynamics simulation.","PeriodicalId":48655,"journal":{"name":"Microscopy","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2022-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41614649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Scanning electron microscopy of Escherichia coli encapsulated in a spacerized graphene sandwich. 用扫描电子显微镜观察包裹在石墨烯夹层中的大肠杆菌。

IF 1.8 4区工程技术

Microscopy Pub Date : 2022-02-26 DOI: 10.1093/jmicro/dfac010

Yuki Sasaki, S. Hirayama, R. Nakao

引用次数: 0

The 70th anniversary issue: Preface. 70周年纪念:前言。

IF 1.8 4区工程技术

Microscopy Pub Date : 2022-02-18 DOI: 10.1093/jmicro/dfab056

S. Okabe

引用次数: 0

Advances in ultrahigh-energy resolution EELS: phonons, infrared plasmons and strongly coupled modes. 超高能量分辨率EELS的进展：声子、红外等离子体激元和强耦合模式。

IF 1.8 4区工程技术

Microscopy Pub Date : 2022-02-18 DOI: 10.1093/jmicro/dfab050

M. Lagos, I. Bicket, S. Mousavi M, G. Botton

{"title":"Advances in ultrahigh-energy resolution EELS: phonons, infrared plasmons and strongly coupled modes.","authors":"M. Lagos, I. Bicket, S. Mousavi M, G. Botton","doi":"10.1093/jmicro/dfab050","DOIUrl":"https://doi.org/10.1093/jmicro/dfab050","url":null,"abstract":"Nowadays, sub-50 meV atom-wide electron probes are routinely produced for electron energy loss spectroscopy in transmission electron microscopes due to monochromator technology advances. We review how gradual improvements in energy resolution enabled the study of very low-energy excitations such as lattice phonons, molecular vibrations, infrared plasmons and strongly coupled hybrid modes in nanomaterials. Starting with the theoretical framework needed to treat inelastic electron scattering from phonons in solids, we illustrate contributions in detecting optical surface phonons in photonic structures. We discuss phonon mapping capabilities in real and reciprocal space, and the localized phonon response near nano-/atomic-scale structural features. We also survey the progress of aloof spectroscopy in studying vibrations in organic materials and applications in measuring local temperature and photonic density of states in single nanostructures using phonon scattering. We then turn towards studies on infrared plasmons in metals and semiconductors. Spectroscopy analyses now extend towards probing extremely complex broadband platforms, the effects of defects and nanogaps, and some far-reaching investigations towards uncovering plasmon lifetime and 3D photonic density of states. In doped semiconductors, we review research on the use of the electron probe to correlate local doping concentration and atomic-scale defects with the plasmonic response. Finally, we discuss advances in studying strong coupling phenomena in plasmon-exciton and plasmon-phonon systems. Overall, the wealth of information gained extends our knowledge about nanomaterial properties and elementary excitations, illustrating the powerful capabilities of high-energy resolution scanning transmission electron microscopy-electron energy loss spectrometry.","PeriodicalId":48655,"journal":{"name":"Microscopy","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2022-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44622865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 16

Imaging neural circuit pathology of autism spectrum disorders: autism-associated genes, animal models and the application of in vivo two-photon imaging. 自闭症谱系障碍的神经回路病理成像:自闭症相关基因、动物模型和体内双光子成像的应用。

IF 1.8 4区工程技术

Microscopy Pub Date : 2022-02-18 DOI: 10.1093/jmicro/dfab039

H. Terashima, Keiichiro Minatohara, Hisato Maruoka, S. Okabe

引用次数: 1

Electron microscopic visualization of single molecules by tag-mediated metal particle labeling. 通过标签介导的金属颗粒标记的单分子的电镜可视化。

IF 1.8 4区工程技术

Microscopy Pub Date : 2022-02-18 DOI: 10.1093/jmicro/dfab048

R. Shigemoto

{"title":"Electron microscopic visualization of single molecules by tag-mediated metal particle labeling.","authors":"R. Shigemoto","doi":"10.1093/jmicro/dfab048","DOIUrl":"https://doi.org/10.1093/jmicro/dfab048","url":null,"abstract":"Genetically encoded tags have introduced extensive lines of application from purification of tagged proteins to their visualization at the single molecular, cellular, histological and whole-body levels. Combined with other rapidly developing technologies such as clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) system, proteomics, super-resolution microscopy and proximity labeling, a large variety of genetically encoded tags have been developed in the last two decades. In this review, I focus on the current status of tag development for electron microscopic (EM) visualization of proteins with metal particle labeling. Compared with conventional immunoelectron microscopy using gold particles, tag-mediated metal particle labeling has several advantages that could potentially improve the sensitivity, spatial and temporal resolution, and applicability to a wide range of proteins of interest (POIs). It may enable researchers to detect single molecules in situ, allowing the quantitative measurement of absolute numbers and exact localization patterns of POI in the ultrastructural context. Thus, genetically encoded tags for EM could revolutionize the field as green fluorescence protein did for light microscopy, although we still have many challenges to overcome before reaching this goal.","PeriodicalId":48655,"journal":{"name":"Microscopy","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2022-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60920361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Analytical technique for self-absorption structure of iron L-emission spectra obtained by soft X-ray emission spectrometer 软x射线发射光谱仪获得的铁l发射光谱的自吸收结构分析技术

IF 1.8 4区工程技术

Microscopy Pub Date : 2022-02-17 DOI: 10.1093/jmicro/dfac009

T. Yokoyama, H. Takahashi, S. Koshiya, T. Murano, M. Terauchi

{"title":"Analytical technique for self-absorption structure of iron L-emission spectra obtained by soft X-ray emission spectrometer","authors":"T. Yokoyama, H. Takahashi, S. Koshiya, T. Murano, M. Terauchi","doi":"10.1093/jmicro/dfac009","DOIUrl":"https://doi.org/10.1093/jmicro/dfac009","url":null,"abstract":"Abstract The method deriving the L self-absorption spectrum from Lα,β emission spectra obtained at different accelerating voltages has been optimized for analyzing the chemical state of Fe in solid materials. Fe Lα,β emission spectra obtained are fitted using Pseudo-Voigt functions and normalized by the integrated intensity of each Fe Ll line, which is not affected by L2,3 absorption edge. The self-absorption spectrum is calculated by dividing the normalized intensity profile collected at low accelerating voltage by that collected at a higher accelerating voltage. The obtained profile is referred to as soft X-ray self-absorption structure (SX-SAS). This method is applied to six Fe-based materials (Fe metal, FeO, Fe3O4, Fe2O3, FeS and FeS2) to observe different chemical states of Fe in those materials. By comparing the self-absorption spectra of iron oxides, one can observe the L3 absorption peak structure shows a shift to the higher energy side as ferric (3+) Fe increases with respect to ferrous (+2) Fe. The intensity profiles of self-absorption spectra of metallic Fe and FeS2 shows shoulder structures between the L3 and L2 absorption peaks, which were not observed in spectra of Fe oxides. These results indicate that the SX-SAS technique is useful to examine X-ray absorption structure as a means to understand the chemical states of transition metal elements.","PeriodicalId":48655,"journal":{"name":"Microscopy","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2022-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47496946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Classification for transmission electron microscope images from different amorphous states using persistent homology 利用持久同源性对不同非晶态透射电子显微镜图像进行分类

IF 1.8 4区工程技术

Microscopy Pub Date : 2022-02-16 DOI: 10.1093/jmicro/dfac008

Fumihiko Uesugi, M. Ishii

引用次数: 1

Inhibition of retinoid X receptor improved the morphology, localization of desmosomal proteins and paracellular permeability in three-dimensional cultures of mouse keratinocytes 维甲酸X受体的抑制改善了三维培养的小鼠角质形成细胞的形态、桥粒蛋白的定位和细胞旁通透性

IF 1.8 4区工程技术

Microscopy Pub Date : 2022-02-16 DOI: 10.1093/jmicro/dfac007

Shoko Ishikawa, M. Nikaido, Takahito Otani, Kayoko Ogata, H. Iida, Yuko Inai, Sachio Tamaoki, T. Inai

{"title":"Inhibition of retinoid X receptor improved the morphology, localization of desmosomal proteins and paracellular permeability in three-dimensional cultures of mouse keratinocytes","authors":"Shoko Ishikawa, M. Nikaido, Takahito Otani, Kayoko Ogata, H. Iida, Yuko Inai, Sachio Tamaoki, T. Inai","doi":"10.1093/jmicro/dfac007","DOIUrl":"https://doi.org/10.1093/jmicro/dfac007","url":null,"abstract":"Abstract Retinoic acid (RA) plays an important role in epithelial homeostasis and influences the morphology, proliferation, differentiation and permeability of epithelial cells. Mouse keratinocytes, K38, reconstituted non-keratinized stratified epithelium in three-dimensional (3D) cultures with serum, which contains retinol (a source of RA), but the morphology was different from in vivo epithelium. The formed epithelium was thick, with loosened cell–cell contacts. Here, we investigated whether the inhibition of RA receptor (RAR)/retinoid X receptor (RXR)-mediated signaling by an RXR antagonist, HX 531, improved K38 3D cultures in terms of morphology and intercellular junctions. The epithelium formed by 0.5 μM HX531 was thin, and the intercellular space was narrowed because of the restoration of the layer-specific distribution of desmoglein (DSG)-1, DSG3 and plakoglobin (PG). Moreover, the levels of desmosomal proteins and tight junction proteins, including DSG1, DSG2, DSG3, PG, claudin (CLDN)-1 and CLDN4 increased, but the adherens junction protein, E-cadherin, did not show any change. Furthermore, CLDN1 was recruited to occludin-positive cell–cell contacts in the superficial cells and transepithelial electrical resistance was increased. Therefore, K38 3D cultures treated with 0.5 μM HX531 provides a useful in vitro model to study intercellular junctions in the non-keratinized epithelium.","PeriodicalId":48655,"journal":{"name":"Microscopy","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2022-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42852543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Machine-learning-based quality-level-estimation system for inspecting steel microstructures 基于机器学习的钢组织检测质量水平估计系统

IF 1.8 4区工程技术

Microscopy Pub Date : 2021-07-25 DOI: 10.1093/jmicro/dfac019

Hiromi Nishiura, A. Miyamoto, Akira Ito, Shogo Suzuki, Kouhei Fujii, Hiroshi Morifuji, Hiroyuki Takatsuka

引用次数: 2