Three-dimensional characteristics of alveolar macrophages in vitro observed by dark field microscopy

2014 ◽  
Author(s):  
Dominic Swarat ◽  
Martin Wiemann ◽  
Hans-Gerd Lipinski
Keyword(s):  
Alveolar Macrophages ◽  
Three Dimensional ◽  
Dark Field ◽  
Dark Field Microscopy

scholarly journals Three-Dimensional Tracking of Chlamydomonas in Dark Field Microscopy

2013 ◽  
Vol 31 (10) ◽  
pp. 1028-1035 ◽  
Author(s):  
Yusuke Arai ◽  
Ken-ichi Wakabayashi ◽  
Masahide Kikkawa ◽  
Hiromasa Oku ◽  
Masatoshi Ishikawa
Keyword(s):  
Three Dimensional ◽  
Dark Field ◽  
Dark Field Microscopy

scholarly journals OBSERVATIONS ON A SUBMICROSCOPIC BASOPHILIC COMPONENT OF CYTOPLASM

1953 ◽  
Vol 97 (5) ◽  
pp. 727-750 ◽  
Author(s):  
Keith R. Porter
Keyword(s):  
Endoplasmic Reticulum ◽  
Dark Field ◽  
Ground Substance ◽  
Adjacent Cell ◽  
Submicroscopic Structure ◽  
Dark Field Microscopy ◽  
Reticular System ◽  
Living Unit ◽  
Cytoplasmic Ground Substance

The cytoplasmic ground substance of animal tissue cells grown in vitro has been found by electron microscopy to contain, as a part of its submicroscopic structure, a complex reticulum of strands, to be referred to as the endoplasmic reticulum. It has been found in all types of cells extensively studied. The components of this reticular system vary considerably in size and form, apparently in some relation to physiological changes in the cell. Thus in one cell of a culture colony it may be finely divided into strands or canaliculi, 50 to 100 mµ in diameter, whereas in an adjacent cell of the same type the components of the reticulum may be relatively coarse, 600 mµ in diameter, and vesiculated. The membrane, which can be shown to limit the system and separate it from the rest of the ground substance, is similar in thickness to the plasma membrane surrounding the cell. Photomicrographs of living cells taken by phase contrast and dark field microscopy define a structure of similar form and indicate that the reticulum of the electron microscope image has its equivalent in the living unit. Where its component units are sufficiently large, a structure of identical form can be resolved by light microscopy in cells stained with hematoxylin or with toluidine blue. This indicated that the endoplasmic reticulum is to be identified with the basophilic or chromophilic component (the ergastoplasm) of the cytoplasm and that such properties of this component as have been determined by cytochemical methods, such as a high RNA content, may be assigned to this "submicroscopic" system.

scholarly journals Three-Dimensional Real-Time Imaging of Gliding Motility in Apicomplexan Parasites using 4D Dark Field Microscopy

2012 ◽  
Vol 102 (3) ◽  
pp. 192a
Author(s):  
James M. Kelvin ◽  
Thomas P. Darlington ◽  
Jose A. Rodriguez ◽  
Reza Zarinshenas ◽  
Yunfei (Even) Zou ◽  
...  
Keyword(s):  
Real Time ◽  
Three Dimensional ◽  
Dark Field ◽  
Gliding Motility ◽  
Real Time Imaging ◽  
Apicomplexan Parasites ◽  
Dark Field Microscopy

scholarly journals Active movement in vitro of bundle of microfilaments isolated from Nitella cell.

1980 ◽  
Vol 87 (3) ◽  
pp. 569-578 ◽  
Author(s):  
S Higashi-Fujime
Keyword(s):  
Actin Filaments ◽  
Dark Field ◽  
Active Movement ◽  
Artificial Medium ◽  
Translational Movement ◽  
Dark Field Microscopy ◽  
Contrast Microscopy ◽  
Subcortical Fibrils

Subcortical fibrils composed of bundles of F-actin filaments and endoplasmic filaments are responsible for endoplasmic streaming. It is reported here that these fibrils and filaments move actively in an artificial medium containing Mg-ATP and sucrose at neutral pH, when the medium was added to the cytoplasm squeezed out of the cell. The movement was observed by phase-contrast microscopy or dark-field microscopy and recorded on 16-mm film. Chains of chloroplasts linked by subcortical fibrils showed translational movement in the medium. Even after all chloroplasts and the endoplasm were washed away by perfusion with fresh medium, free fibrils and/or filaments (henceforth, referred to as fibers) not attached to chloroplasts continued travelling in the direction of the fiber orientation. Sometimes the fibers formed rings and rotated. Chloroplast chains and free fibers or rings continued moving for 5-30 min at about half the rate of the endoplasmic streaming in vivo. Calcium ion concentrations < 10(-7) M permitted movement to take place. Electron microscopy revealed that both fibers and rings were bundles of F-actin filaments that showed the same polarity after decoration with heavy meromyosin.

scholarly journals In Vitro Antimicrobial Susceptibility of Clinical Isolates of Borrelia miyamotoi

2018 ◽  
Vol 62 (7) ◽  
pp. e00419-18 ◽  
Author(s):  
Joris Koetsveld ◽  
Annemijn Manger ◽  
Dieuwertje Hoornstra ◽  
Ronald O. Draga ◽  
Anneke Oei ◽  
...  
Keyword(s):  
Antimicrobial Susceptibility ◽  
Fetal Calf Serum ◽  
Calf Serum ◽  
Dark Field ◽  
Clinical Isolates ◽  
Borrelia Miyamotoi ◽  
Content Type ◽  
Dark Field Microscopy ◽  
Made In

ABSTRACT Borrelia miyamotoi is an emerging relapsing fever (RF) Borrelia species that is reported to cause human disease in regions in which Lyme borreliosis is endemic. We recently showed that B. miyamotoi tick isolates are resistant to amoxicillin in vitro; however, clinical isolates have not been studied. Therefore, our aim was to show the antimicrobial susceptibility of recently obtained clinical isolates of B. miyamotoi. A dilution series of various antibiotics was made in modified Kelly-Pettenkofer medium with 10% fetal calf serum. The susceptibilities of different B. miyamotoi clinical, B. miyamotoi tick, RF Borrelia, and Borrelia burgdorferi sensu lato isolates were tested by measuring MICs through colorimetric changes and by counting motile spirochetes by dark-field microscopy after 72 h of incubation. The ceftriaxone and azithromycin MIC ranges of the six B. miyamotoi clinical isolates tested were 0.03 to 0.06 mg/liter and 0.0016 to 0.0032 mg/liter, respectively. These values are similar to MICs for RF Borrelia strains and B. miyamotoi tick isolates. All tested RF Borrelia strains were susceptible to doxycycline (microscopic MIC range, 0.0625 to 0.25 mg/liter). In contrast to the MICs of the tested B. burgdorferi sensu lato strains and in line with our previous findings, the amoxicillin MICs (range, 8 to 32 mg/liter) of all RF Borrelia strains, including B. miyamotoi clinical isolates, were above the clinical breakpoint for resistance (≤4 mg/liter). Clinical isolates of B. miyamotoi are highly susceptible to doxycycline, azithromycin, and ceftriaxone in vitro. Interestingly, as described previously for tick isolates, amoxicillin shows poor in vitro activity against B. miyamotoi clinical isolates.

scholarly journals Comparative characteristics of various fibrous materials in in vitro experiments

2021 ◽  
Vol 102 (4) ◽  
pp. 501-509
Author(s):  
G A Timerbulatova ◽  
P D Dunaev ◽  
A M Dimiev ◽  
G F Gabidinova ◽  
N N Khaertdinov ◽  
...  
Keyword(s):  
Cell Cultures ◽  
Morphological Characteristics ◽  
Single Walled Carbon Nanotubes ◽  
Bronchial Epithelium ◽  
Dark Field ◽  
Fibrous Materials ◽  
Chrysotile Asbestos ◽  
Dark Field Microscopy ◽  
Walled Carbon Nanotubes

Aim. Comparative assessment of the effect of fibrous materials on cell cultures RAW264.7 and BEAS-2B. Methods. The effects of various fibrous materials single-walled carbon nanotubes of two types (SWCNT-1 and SWCNT-2), differing in morphological characteristics, and chrysotile asbestos as a positive control was assessed on two cell lines macrophages RAW 264.7 and human bronchial epithelium BEAS-2B cells. The studied materials concentration range for experiments on cells was selected taking into account the SWCNT content in the air of the working area and the subsequent modeling of SWCNT deposition in the human respiratory tract. Suspensions of the studied materials were prepared based on cell culture media by ultrasonication. Cytotoxicity assessment after 48 hours of incubation was performed by using the MTS colorimetric assay. The expression level of apoptosis markers was assessed by immunoblotting using the corresponding monoclonal antibodies. Visualization of SWCNT-1, SWCNT-2 and chrysotile asbestos in BEAS-2B cell cultures was carried out by improved dark-field microscopy. Results. According to dark-field microscopy, all the studied fibrous materials were found on the surface or cytoplasm of the cells. SWCNT and chrysotile asbestos did not have a direct cytotoxic effect in the MTS assay and did not induce apoptosis according to the results of Western blotting in cell cultures of RAW264.7 macrophages and BEAS-2B bronchial epithelium. In the cells of the bronchial epithelium (BEAS-2B) that showed greater sensitivity, a slight increase in the expression of pro-apoptotic protein PARP, which was more pronounced for shorter SWCNT-2, was revealed. Conclusion. Both types of SWCNTs, despite the differences in morphological characteristics, demonstrated similar effects in in vitro experiments; this result, with its further verification, can have an important practical application in justifying approaches to determining the safety criteria for single-walled carbon nanotubes as a class of nanomaterials of the same type.

Examination of various cell culture techniques for co-incubation of virulent Treponema pallidum (Nichols I strain) under anaerobic conditions

1976 ◽  
Vol 4 (4) ◽  
pp. 360-371
Author(s):  
P L Sandok ◽  
S T Knight ◽  
H M Jenkin
Keyword(s):  
Cell Culture ◽  
Mammalian Cells ◽  
Culture Medium ◽  
Treponema Pallidum ◽  
Dark Field ◽  
Anaerobic Conditions ◽  
Cell Culture Techniques ◽  
Culture Techniques ◽  
Dark Field Microscopy

Treponema pallidum (Nichols virulent) was incubated with and without cells in cell culture medium reduced to -275 mV Ecal, pH 7.3, under deoxygenated conditions. Five to ten percent of the treponemes attached to cells and remained motile for at least 120 h in cell-treponeme systems of co-incubation. Virulent treponemes could be detected after 120 to 144 h in the supernatant fluids of cell-treponeme co-incubation cultures and in cell-free tubes containing medium harvested from aerobically cultivated mammalian cells. Medium supplemented with ox serum ultrafiltrate, pyruvate, and sodium thioglycolate and gas mixtures containing H2 and CO2 enhanced treponemal survival. Increases in treponemal numbers were observed using dark-field microscopy but were not substantiated using the rabbit lesion test. Continuous passage of the treponeme was not achieved in vitro.

Ultrastructural Investigations of the Contractile Filaments of Amoebae

1974 ◽  
Vol 32 ◽  
pp. 188-189
Author(s):  
P.L. Moore
Keyword(s):  
Cytoplasmic Streaming ◽  
Three Dimensional ◽  
Freeze Fracture ◽  
Amoeboid Movement ◽  
Different Types ◽  
Chemical Conditions ◽  
Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

Elastic Scattering in Electron Microscopy

1973 ◽  
Vol 31 ◽  
pp. 252-253
Author(s):  
J. Langmore ◽  
M. Isaacson ◽  
J. Wall ◽  
A. V. Crewe
Keyword(s):  
Electron Microscopy ◽  
Elastic Scattering ◽  
Cross Section ◽  
Quantum Noise ◽  
Dark Field ◽  
Elastic Cross Section ◽  
Biological Molecules ◽  
Dark Field Microscopy ◽  
Field Systems ◽  
Effects Of Radiation

High resolution dark field microscopy is becoming an important tool for the investigation of unstained and specifically stained biological molecules. Of primary consideration to the microscopist is the interpretation of image Intensities and the effects of radiation damage to the specimen. Ignoring inelastic scattering, the image intensity is directly related to the collected elastic scattering cross section, σɳ, which is the product of the total elastic cross section, σ and the eficiency of the microscope system at imaging these electrons, η. The number of potentially bond damaging events resulting from the beam exposure required to reduce the effect of quantum noise in the image to a given level is proportional to 1/η. We wish to compare η in three dark field systems.

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