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Published in Anton Sebastian, A Dictionary of the History of Medicine, 2018
Ultramicroscope [Latin: ultra, beyond; Greek: mikros, small + skopein, to view] Devised by Siedentopf and Richard Adolf Zsigmondy (1866–1930) around 1848. Their instrument projected light from a source on suspended particles in solution which were then viewed on a dark background through the microscope. It was improved by F.H. Wenham who added a dark-field condenser in 1850.
Platelet-derived microparticles stimulated by anti-β2GPI/β2GPI complexes induce pyroptosis of endothelial cells in antiphospholipid syndrome
Published in Platelets, 2023
Longjiang Di, Caijun Zha, Yanhong Liu
Microparticles (MPs) have gained a fair amount of attention because of their important role in inflammation, prothrombotic states, and autoimmune diseases [7–11]. MPs are ultramicroscopic membranous vesicles with a diameter of approximately 0.05–1 μm. Several types of MPs exist in the human body, including platelet, endothelial cells, and erythrocyte-derived particles [12]. Platelet-derived microparticles (PMPs) are the most abundant, accounting for approximately 70–90% of circulating MPs [13]. PMPs are very small membranous vesicles released outside the cell after platelet stimulation. These vesicles can carry a markers of the parent cell, such as phosphatidylserine, lipids, and membrane proteins on their surface, and participate in intracellular communication by transferring proteins, mRNAs, and microRNAs to target cells [14,15]. PMPs can cause inflammatory responses directly by promoting neutrophil activation and adhesion to the endothelium [16]. Increasing evidence indicates that PMPs may have efficient pro-coagulant and pro-inflammatory activities in autoimmune diseases [9,17]. Nonetheless, our team and others have demonstrated that IC can stimulate aberrant PMPs activation through the toll-like receptor (TLR)4/p38 signaling pathway by binding to TLR4 on platelets, which releases PMPs [18]. However, the possibility that PMPs stimulated by IC (IC-PMPs) may lead to inflammatory damage of APS endothelial cells has should be further investigated.
The sub-acute toxicity of kavalactone in rats: a study of the effect of oral doses and the mechanism of toxicity in combination with ethanol
Published in Drug and Chemical Toxicology, 2023
Mohammed Abdulabbas Hasan, Syam Mohan, Heshu Sulaiman Rahman, Hemn Hasan Othman, Shirwan Hamasalih Omer, Abdullah Farasani
Hepatocytes were further examined and assessed in detail, at the ultramicroscopic level by TEM evaluation. The liver from rats of the control groups displayed the normal morphological appearance of hepatic and Kupffer cells. Hepatocytes displayed a large round nucleus with the normal distribution of heterochromatin, round mitochondria, intact endoplasmic reticulum, and peroxisomes. Generally, in the liver of 800 mg/ kg bw, po KL-intoxicated rats (alone or in combination with EtOH), ongoing cystic and fatty degeneration, hypertrophic and necrotic changes were observed, comprising of abnormal nuclei, vacuolations, fragmentation, and dispersed cytoplasmic organelles. Distinct changes in organelles consisted of, mitochondriopathy characterized by a swollen mitochondrion, with either cristorrhexis or cristolysis as prominent changes, in addition to numerous swollen lysosomes. Markedly swollen mitochondria appeared interspersed with either disorganized rough endoplasmic reticulum (rER) or dilated/well-developed rER cisternae. High proliferation of peroxisomes and expansion of smooth endoplasmic reticulum (sER) have been shown to occur especially at the perinuclear endoplasmic reticulum, with clear hypertrophic Kupffer cells (Figure 4).
A quick and versatile protocol for the 3D visualization of transgene expression across the whole body of larval Drosophila
Published in Journal of Neurogenetics, 2021
Oliver Kobler, Aliće Weiglein, Kathrin Hartung, Yi-chun Chen, Bertram Gerber, Ulrich Thomas
Tiled image stacks were acquired on an UltraMicroscope II (Miltenyi Biotec, Bergisch-Gladbach, Germany) equipped with a Zyla 4.2 PLUS SCMOS camera (Oxford Instruments, Abingdon-on-Thames, UK). The setup was equipped either with an Olympus zoom body and a MVPLAPO 2 × 0.5 NA dipping objective (Olympus, Tokyo, Japan) or an ultramicroscope tube for infinity-corrected objective lenses and a magnification changer, which allows for an additional 2x magnification. The dipping objectives for the tube were an LVMI-Fluor 4X/0.3 and an LVMI-Fluor 12X/0.53 (both from Miltenyi Biotec, Bergisch-Gladbach, Germany), or an HCX APO 20X/0.95 IMM (Leica Microsystems, Wetzlar, Germany). These objectives are suitable for imaging in ECi by matching its refractive index (RI) of 1.558. Furthermore, they provide a large working distance. Light from a supercontinuum EXW-12 extreme laser (NKT Photonics, Birkerød, Denmark) was guided through excitation filters (AHF Analysentechnik AG, Tübingen, Germany) and through triple sheet optics to illuminate samples from either just one side or from both sides. For data acquisition ImSpector software (version 5.0.285 − 7.0.124, Miltenyi Biotec, Bergisch-Gladbach, Germany) was used. Images acquired using two-side illumination were automatically fused with the built-in blend algorithm. In some cases, the built-in dynamic focusing function was used to achieve uniform z-resolution across the width (X-axis) of the sample. Resulting image parts were fused automatically through the built-in contrast adaptive algorithm. For all images presented in this study, acquisition parameters such as filters, objectives, z-slice numbers, z-step sizes, number of tiles, and exposure times are provided in Supplementary Table 1. With a format of 2048 × 2048 and the bit-depth set to 16-bit, the resulting data size was about 40–70 gigabytes per channel. For stitching, an overlap of tiles by 10% or 15% of the imaging format was used. Depending on the parameter settings, the time taken to image an entire larva varied considerably (Supplementary Table 1).