Telocytes in pleura: two- and three-dimensional imaging by transmission electron microscopy

Information about the ultrastructure of connective (interstitial) cells supporting the pleural mesothelium is scarce. Our aim has been to examine whether telocytes (TCs) are present in pleura, as in epicardium and mesentery. TCs are a distinct type of cell, characterized by specific prolongations named telopodes (Tp). We have used transmission electron microscopy (TEM) and electron tomography (ET) to determine whether ultrastructural diagnostic criteria accepted for TCs are fulfilled by any of the cell subpopulations existing in the sub-mesothelial layer in mouse and human pleura. TCs have been identified with TEM by their characteristic prolongations. Tp appear long and moniliform, because of the alternation of podomeres (thin segments of less than 0.2 μm) and podoms (small dilations accommodating caveolae, mitochondria, and endoplasmic reticulum). Tp ramifications follow a dichotomic pattern and establish specialized cell-to-cell junctional complexes. TCs, via their Tp, seem to form an interstitial network beneath the mesothelium, covering about two-thirds of the abluminal mesothelial layer. ET has revealed complex junctional structures and tight junctions connecting pleural TCs, and small vesicles at this level in Tp. Thus, pleural TCs share significant similarities with TCs described in other serosae. Whether TCs are a (major) player in mesothelial-cell-induced tissue repair remains to be established. Nevertheless, the extremely long thin Tp and complex junctional structures that they form and the release of vesicles (or exosomes) indicate the participation of TCs in long-distance homo- or heterocellular communication

Telocytes and putative stem cells in the lungs: electron microscopy, electron tomography and laser scanning microscopy

This study describes a novel type of interstitial (stromal) cell — telocytes (TCs) — in the human and mouse respiratory tree (terminal and respiratory bronchioles, as well as alveolar ducts). TCs have recently been described in pleura, epicardium, myocardium, endocardium, intestine, uterus, pancreas, mammary gland, etc. (see www.telocytes.com). TCs are cells with specific prolongations called telopodes (Tp), frequently two to three per cell. Tp are very long prolongations (tens up to hundreds of μm) built of alternating thin segments known as podomers (≤ 200 nm, below the resolving power of light microscope) and dilated segments called podoms, which accommodate mitochondria, rough endoplasmic reticulum and caveolae. Tp ramify dichotomously, making a 3-dimensional network with complex homo- and heterocellular junctions. Confocal microscopy reveals that TCs are c-kit- and CD34-positive. Tp release shed vesicles or exosomes, sending macromolecular signals to neighboring cells and eventually modifying their transcriptional activity. At bronchoalveolar junctions, TCs have been observed in close association with putative stem cells (SCs) in the subepithelial stroma. SCs are recognized by their ultrastructure and Sca-1 positivity. Tp surround SCs, forming complex TC-SC niches (TC-SCNs). Electron tomography allows the identification of bridging nanostructures, which connect Tp with SCs. In conclusion, this study shows the presence of TCs in lungs and identifies a TC-SC tandem in subepithelial niches of the bronchiolar tree. In TC-SCNs, the synergy of TCs and SCs may be based on nanocontacts and shed vesicles

Impact of Intermediate Hyperglycemia and Diabetes on Immune Dysfunction in Tuberculosis

Supplementary Data: Supplementary materials are available at Clinical Infectious Diseases online at https://academic.oup.com/cid/article/72/1/69/5857148#274319223 . Consisting of data provided by the authors to benefit the reader, the posted materials are not copyedited and are the sole responsibility of the authors, so questions or comments should be addressed to the corresponding author.Copyright © The Author(s) 2020. Background: People with diabetes have an increased risk of developing active tuberculosis (TB) and are more likely to have poor TB-treatment outcomes, which may impact on control of TB as the prevalence of diabetes is increasing worldwide. Blood transcriptomes are altered in patients with active TB relative to healthy individuals. The effects of diabetes and intermediate hyperglycemia (IH) on this transcriptomic signature were investigated to enhance understanding of immunological susceptibility in diabetes-TB comorbidity. Methods: Whole blood samples were collected from active TB patients with diabetes (glycated hemoglobin [HbA1c] ≥6.5%) or IH (HbA1c = 5.7% to <6.5%), TB-only patients, and healthy controls in 4 countries: South Africa, Romania, Indonesia, and Peru. Differential blood gene expression was determined by RNA-seq (n = 249). Results: Diabetes increased the magnitude of gene expression change in the host transcriptome in TB, notably showing an increase in genes associated with innate inflammatory and decrease in adaptive immune responses. Strikingly, patients with IH and TB exhibited blood transcriptomes much more similar to patients with diabetes-TB than to patients with only TB. Both diabetes-TB and IH-TB patients had a decreased type I interferon response relative to TB-only patients. Conclusions: Comorbidity in individuals with both TB and diabetes is associated with altered transcriptomes, with an expected enhanced inflammation in the presence of both conditions, but also reduced type I interferon responses in comorbid patients, suggesting an unexpected uncoupling of the TB transcriptome phenotype. These immunological dysfunctions are also present in individuals with IH, showing that altered immunity to TB may also be present in this group. The TB disease outcomes in individuals with IH diagnosed with TB should be investigated further.European Union’s Seventh Framework Programme (FP7 2007-2013 - Health) under grant agreement No 305279

Effect of BaZrO(3) Inclusions on the Microwave Surface Impedance of YBCO Films in a Magnetic Field

We perform measurements of high-frequency (similar to 48 GHz) microwave surface impedance with an applied magnetic field in YBa(2)Cu(3)O(7-delta) ( YBCO) laser-ablated films with various amounts of BaZrO(3) ( BZO) sub-micrometric inclusions, up to 7 mol % concentration. BZO inclusions are very effective in the reduction of the field-induced surface resistance in our experimentally accessible field range [ 0, 0.8] T. At temperatures low enough, the application of a moderate (similar to 0.2 T) field makes the YBCO/BZO films markedly less dissipative than pure YBCO. This result, examined in the light of the very high measuring frequency ( very small vortex oscillation amplitude) shows that BZO inclusions are even more effective pinning centers than columnar defects. We study the dependence of the vortex parameters ( vortex viscosity, pinning constant) on the BZO concentration. We examine the correlation between the reduction of the microwave dissipation and the areal density of BZO-induced defects. We argue that the very improved performances in a magnetic field are due to individual pinning of vortices on BZO inclusions

Ordered misfit dislocations in epitaxial Gd doped CeO 2 thin films deposited on (001)YSZ single crystal substrates

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Epitaxial growth and characterization of La2Zr2O 7 multilayers on biaxially textured NiW substrate by chemical solution deposition under highly reducing conditions

The paper presents the growth and characterization of highly textured La2Zr2O7 (LZO) multilayer coatings on Ni-5 at.%W (NiW) biaxially textured substrates by chemical solution deposition (CSD) under highly reducing conditions (Ar + 12%H2) in order to protect the metallic substrate from oxidation. The coating solution consists in a stoichiometric mixture of lanthanum and zirconium acetylacetonates dissolved in an excess of propionic acid. The precursor chemistry was studied by means of infrared spectroscopy, thermogravimetric-differential thermal analyses, Raman spectroscopy and X-ray diffraction carried out on the precursor powder. The as-grown multilayer LZO coating exhibits a sharp in-plane and out-of-plane texture, with the full-width-at-half-maximum of the \u3c9-scans and \u3c6-scans of about 7.2 and 8.0, respectively, close to that of the NiW substrate. The volume fraction of the c-axis oriented grains from the top layer of the coating increases with the number of layers. The LZO coating exhibits a smooth and crack-free surface, appropriate for the further epitaxial growth of a seed layer for the YBa2Cu3O7 - x (YBCO) deposition. Transmission Electron Microscopy was used to investigate the microstructure of the CSD LZO thin films deposited on flexible NiW substrates. A high density of nanovoids, with a size ranging between 10 and 30 nm, was observed in the LZO layers. YBCO films epitaxially grown by pulsed laser deposition on the CSD LZO buffer layer exhibit critical current densities, Jc, close to 1.6 MA/cm2 at 77 K and self-field and zero resistance critical temperature (Tc(R = 0)) of 90.3 K

Microwave properties of YBCO films with BZO nanoinclusions

We present measurements of the microwave complex surface impedance at 47.7 GHz in YBa2Cu3O7Àd (YBCO) films deposited by pulsed laser deposition with the explicit goal to introduce BaZrO3 (BZO) nanoinclusions. Composite targets obtained by addition of BZO powder in molar percents ranging from 2.5 to 7 mol.% have been prepared and characterized. Measurements of the microwave surface impedance indicate a broadened transition in zero field, however compensated by a very large pinning frequency, indicating that while intergrain properties are still to be optimized the effect of nanometric inclusions substantially enhances the intragrain vortex pinning