scholarly journals A systematic characterization of intrinsically formed microglia-like cells during retinal organoid differentiation.

2022 ◽  
Author(s):  
Katarina Bartalska ◽  
Verena Hübschmann ◽  
Medina Korkut-Demirbaş ◽  
Ryan John Abat Cubero ◽  
Alessandro Venturino ◽  
...  
Keyword(s):  
Protein Composition ◽  
Human Microglia ◽  
Development Organization ◽  
Cellular Environment ◽  
Preferential Localization ◽  
Circuit Development ◽  
And Migration ◽  
Induced Pluripotent ◽  
Insight Into

Brain organoids differentiated from human induced pluripotent stem cells provide a unique opportunity to investigate the development, organization and connectivity of neurons in a complex cellular environment. However, organoids usually lack microglia, brain-resident immune cells which are both present in the early human embryonic brain and participate in neuronal circuit development. Here, we find that microglia innately develop in unguided retinal organoid differentiation between week 3 and 4 in 2.5D culture and appear later in floating, non-pigmented, 3D-cystic compartments. We enriched for cystic structures using a low-dosed BMP4 application and performed mass spectrometry, thus defining the protein composition of microglia-containing compartments. We found that cystic compartments expressed both mesenchymal and epithelial markers with microglia enriched in the mesenchymal region. Interestingly, microglia-like cells started to express the border-associated macrophage marker CD163. The preferential localization of human microglia to a mesenchymal compartment provides insight into the behavior and migration of microglia. The model will ultimately allow detailed study of these enigmatic cells and how they enter and distribute within the human brain.

Surface Chemical Characterization of Internal Interfaces Generated Within Thin-Film Fe-Ti Hydrides

1987 ◽  
Vol 111 ◽  
Author(s):  
Jeffrey H. Sanders ◽  
Bruce J. Tatarchuk
Keyword(s):  
Depth Profiling ◽  
Chemical Characterization ◽  
Decomposition Process ◽  
Surface Chemical ◽  
State Information ◽  
Size Information ◽  
Excellent Candidate ◽  
And Migration ◽  
Insight Into

AbstractFeTi is considered an excellent candidate for the reversible storage of hydrogen and has been studied extensively in an attempt to understand the bulk activation needed for this material before use. Segregation of TiO2 to the surface has been noted to occur during activation explaining a slight loss of efficiency per hydride cycle, however, characterization by a host of bulk and surface sensitive techniques has not revealed the cause of this decomposition process.10 nm FeTi samples were prepared in a UHV evaporator both with and without palladium coatings. Post treatment characterization was performed with backscatter conversion electron Mossbauer spectroscopy (CEMS), XPS and SIMS. CEMS is a powerful tool for providing stoichiometric, electronic, magnetic, chemical, and particle size information of iron at depths down to 100 nm. XPS and SIMS are useful to gain quantitative and chemical state information from the topmost 2 nm and the topmost monolayer, respectively. Activation treatments consisted of annealing at 573K and 623K followed by reduction at 573K. Results indicate that ppm levels of H2O in H2 are sufficient to decompose the FeTi alloy and produce TiO2 and Fe metal domains at the surface. Also, at 573K in vacuum, a solid-state reaction was found to occur between Fe oxides and FeTi to produce Fe metal and TiO2. The Pd-FeTi interface was probed with CEMS and the results demonstrate hydrogen dissociation and migration in the absence of alloy decomposition. Our approach uses nondestructive-depth profiling of non-Pd coated FeTi samples along with interfacial information from Pd-FeTi specimens to obtain unique insight into the decomposition process.

scholarly journals Interference of pH buffer with Pb2+-peripheral domain interactions: obstacle or opportunity?

2020 ◽  
Author(s):  
Sachin Katti ◽  
Tatyana I. Igumenova
Keyword(s):  
Binding Sites ◽  
Metal Ion ◽  
Functional Characterization ◽  
Valuable Insight ◽  
Cellular Environment ◽  
Domain Interactions ◽  
Ph Buffer ◽  
Insight Into ◽  
Peripheral Domain

ABSTRACTPb2+ is a xenobiotic metal ion that competes for Ca2+-binding sites in proteins. Using the peripheral Ca2+-sensing domains of Syt1, we show that the chelating pH buffer Bis-Tris enables identification and functional characterization of high-affinity Pb2+ sites that are likely to be targeted by bioavailable Pb2+.Significance to MetallomicsSyt1, a key regulator of Ca2+-evoked neurotransmitter release, is a putative molecular target of Pb2+. We demonstrate that the use of a chelating pH buffer Bis-Tris enables identification of Ca2+-binding sites that would be most susceptible to Pb2+ attack in the cellular environment. In addition, experiments conducted in Bis-Tris revealed the differences between the membrane-binding responses of two Ca2+-sensing domains of Syt1, C2A and C2B. This work advances the understanding of how Pb2+ interacts with multipartite Ca2+-binding sites, and illustrates that conducting the experiments under both chelating and non-chelating conditions could provide valuable insight into the mechanism of metallosensory proteins.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

Derivation and Characterization of human Induced Pluripotent Stem Cells

Acta Naturae ◽  
2009 ◽  
Vol 1 (2) ◽  
pp. 91-92 ◽  
Author(s):  
M V Shutova ◽  
A N Bogomazova ◽  
M A Lagarkova ◽  
S L Kiselev
Keyword(s):  
Stem Cells ◽  
Induced Pluripotent Stem Cells ◽  
Pluripotent Stem Cells ◽  
Induced Pluripotent

scholarly journals LINC01089 suppresses lung adenocarcinoma cell proliferation and migration via miR-301b-3p/STARD13 axis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ye Qian ◽  
Yan Zhang ◽  
Haoming Ji ◽  
Yucheng Shen ◽  
Liangfeng Zheng ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Lung Adenocarcinoma ◽  
High Morbidity ◽  
Lipid Transfer ◽  
Protein Coding ◽  
Cell Proliferation And Migration ◽  
Reduce Cell Proliferation ◽  
And Migration ◽  
Insight Into ◽  
Proliferation And Migration

Abstract Background Lung adenocarcinoma (LUAD) is one of the most common cancers with high morbidity and mortality worldwide. Long non-coding RNAs (lncRNAs) serve as tumor promoters or suppressors in the development of various human malignancies, including LUAD. Although long intergenic non-protein coding RNA 1089 (LINC01089) suppresses the progression of breast cancer, its mechanism in LUAD requires further exploration. Thus, we aimed to investigate the underlying function and mechanism of LINC01089 in LUAD. Methods The expression of LINC01089 in LUAD and normal cell lines was detected. Functional assays were applied to measure cell proliferation, apoptosis and migration. Besides, mechanism experiments were employed for assessing the interplay among LINC01089, miR-301b-3p and StAR related lipid transfer domain containing 13 (STARD13). Data achieved in this study was statistically analyzed with Student’s t test or one-way analysis of variance. Results LINC01089 expression was significantly down-regulated in LUAD tissues and cells and its overexpression could reduce cell proliferation and migration. Moreover, LINC01089 could regulate STARD13 expression through competitively binding to miR-301b-3p in LUAD. Additionally, rescue assays uncovered that STARD13 depletion or miR-301b-3p overexpression could countervail the restraining effect of LINC01089 knockdown on the phenotypes of LUAD cells. Conclusion LINC01089 served as a tumor-inhibitor in LUAD by targeting miR-301b-3p/STARD13 axis, providing an innovative insight into LUAD therapies. Trial registration Not applicable.

scholarly journals First Insight into Nutraceutical Properties of Local Salento Cichorium intybus Varieties: NMR-Based Metabolomic Approach

2021 ◽  
Vol 18 (8) ◽  
pp. 4057
Author(s):  
Chiara Roberta Girelli ◽  
Francesca Serio ◽  
Rita Accogli ◽  
Federica Angilè ◽  
Antonella De Donno ◽  
...  
Keyword(s):  
1H Nmr ◽  
Cichorium Intybus ◽  
Resonance Spectroscopy ◽  
Metabolic Profiles ◽  
Whole Plant ◽  
Different Content ◽  
Insight Into ◽  
Nutraceutical Properties ◽  
Metabolomic Approach

Background: Plants of genus Cichorium are known for their therapeutic and nutraceutical properties determined by a wealth of phytochemical substances contained in the whole plant. The aim of this paper was to characterize the metabolic profiles of local Salento chicory (Cichorium intybus L.) varieties (“Bianca”, “Galatina”, “Leccese”, and “Otranto”) in order to describe their metabolites composition together with possible bioactivity and health beneficial properties. Methods: The investigation was performed by 1H-NMR spectroscopy and Multivariate Analysis (MVA), by which the metabolic profiles of the samples were easily obtained and compared. Results: The supervised Partial Least Squares Discriminant Analysis (PLS-DA) analysis showed as “Bianca” and “Galatina” samples grouped together separated by “Leccese” and “Otranto” varieties. A different content of free amino acids and organic acids was observed among the varieties. In particular a high content of cichoric and monocaffeoyl tartaric acid was observed for the “Leccese” variety. The presence of secondary metabolites adds significant interest in the investigation of Cichorium inthybus, as this vegetable may benefit human health when incorporated into the diet. Conclusions: The 1H-NMR (Nuclear Magnetic Resonance Spectroscopy) based characterization of Salento chicory varieties allowed us to determine the potential usefulness and nutraceutical properties of the product, also providing a method to guarantee its authenticity on a molecular scale.

“Real-World” Microscopy: Understanding Environment-Sensitive Behavior of Ni-Base Welds

1998 ◽  
Vol 4 (S2) ◽  
pp. 528-529
Author(s):  
M. G. Burke ◽  
R. J. Wehrer ◽  
C.M. Brown
Keyword(s):  
Nuclear Power ◽  
Base Alloy ◽  
Analytical Electron Microscopy ◽  
Furnace Cool ◽  
Environmental Embrittlement ◽  
Reported Study ◽  
Compositional Changes ◽  
Insight Into ◽  
Sensitive Behavior

Ni-base alloy welds such as EN82H weld metal are frequently employed in nuclear power applications where resistance to corrosion is required. Results of a recently reported study of the mechanical properties of EN82H welds show that this alloy is susceptible to low-temperature (∼100°C) environmental embrittlement (LTEE) in hydrogenated water. LTEE is a manifestation of hydrogen embrittlement in these alloys.1 Recent LTEE tests have demonstrated a beneficial effect of a high-temperature (∼1100°C) anneal and furnace-cool in alleviating the material's susceptibility to LTEE. Understanding the reason for the reduction in LTEE susceptibility requires detailed characterization of the microstructure so that the specific structural and compositional changes that have been induced by the solution-anneal can be identified. This study reports the results of light optical and analytical electron microscopy (AEM) characterization of the microstructures of as-fabricated and as-solution-annealed EN82H welds with the objective of providing insight into the observed LTEE behavior.

scholarly journals Electrodiffusion Phenomena in Neuroscience and the Nernst–Planck–Poisson Equations

Electrochem ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 197-215
Author(s):  
Jerzy J. Jasielec
Keyword(s):  
Electrical Potential ◽  
Signal Propagation ◽  
Liquid Junction Potential ◽  
Liquid Junction ◽  
Patch Clamp Technique ◽  
Poisson Equations ◽  
Cellular Environment ◽  
Electrochemical Transport ◽  
Insight Into ◽  
Junction Potential

This work is aimed to give an electrochemical insight into the ionic transport phenomena in the cellular environment of organized brain tissue. The Nernst–Planck–Poisson (NPP) model is presented, and its applications in the description of electrodiffusion phenomena relevant in nanoscale neurophysiology are reviewed. These phenomena include: the signal propagation in neurons, the liquid junction potential in extracellular space, electrochemical transport in ion channels, the electrical potential distortions invisible to patch-clamp technique, and calcium transport through mitochondrial membrane. The limitations, as well as the extensions of the NPP model that allow us to overcome these limitations, are also discussed.

scholarly journals Exploration of Alternative Splicing Events in Mesenchymal Stem Cells from Human Induced Pluripotent Stem Cells

Genes ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 737
Author(s):  
Ji-Eun Jeong ◽  
Binna Seol ◽  
Han-Seop Kim ◽  
Jae-Yun Kim ◽  
Yee-Sook Cho
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Alternative Splicing ◽  
Functional Enrichment ◽  
Actin Binding ◽  
Pcr Analysis ◽  
Valuable Insight ◽  
Sequencing Analysis ◽  
Induced Pluripotent ◽  
Insight Into

Although comparative genome-wide transcriptomic analysis has provided insight into the biology of human induced pluripotent stem cell-derived mesenchymal stem cells (iMSCs), the distinct alternative splicing (AS) signatures of iMSCs remain elusive. Here, we performed Illumina RNA sequencing analysis to characterize AS events in iMSCs compared with tissue-derived MSCs. A total of 4586 differentially expressed genes (|FC| > 2) were identified between iMSCs and umbilical cord blood-derived MSCs (UCB-MSCs), including 2169 upregulated and 2417 downregulated genes. Of these, 164 differentially spliced events (BF > 20) in 112 genes were identified between iMSCs and UCB-MSCs. The predominant type of AS found in iMSCs was skipped exons (43.3%), followed by retained introns (19.5%), alternative 3′ (15.2%) and 5′ (12.8%) splice sites, and mutually exclusive exons (9.1%). Functional enrichment analysis showed that the differentially spliced genes (|FC| > 2 and BF > 20) were mainly enriched in functions associated with focal adhesion, extracellular exosomes, extracellular matrix organization, cell adhesion, and actin binding. Splice isoforms of selected genes including TRPT1, CNN2, and AP1G2, identified in sashimi plots, were further validated by RT-PCR analysis. This study provides valuable insight into the biology of iMSCs and the translation of mechanistic understanding of iMSCs into therapeutic applications.

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