SEM of non-coated hepatocellular cytoskeleton of perfused livers

1984 ◽  
Vol 42 ◽  
pp. 306-307
Author(s):  
S.W. French ◽  
N.C. Benson ◽  
C. Davis-Scibienski
Keyword(s):  
Ambient Temperature ◽  
Critical Point ◽  
Protease Inhibitors ◽  
Metal Deposition ◽  
Heat Damage ◽  
Detergent Extraction ◽  
Cytoskeletal Elements ◽  
Triton X ◽  
Excised Tissue

Previous SEM studies of liver cytoskeletal elements have encountered technical difficulties such as variable metal coating and heat damage which occurs during metal deposition. The majority of studies involving evaluation of the cell cytoskeleton have been limited to cells which could be isolated, maintained in culture as a monolayer and thus easily extracted. Detergent extraction of excised tissue by immersion has often been unsatisfactory beyond the depth of several cells. These disadvantages have been avoided in the present study. Whole C3H mouse livers were perfused in situ with 0.5% Triton X-100 in a modified Jahn's buffer including protease inhibitors. Perfusion was continued for 1 to 2 hours at ambient temperature. The liver was then perfused with a 2% buffered gluteraldehyde solution. Liver samples including spontaneous tumors were then maintained in buffered gluteraldehyde for 2 hours. Samples were processed for SEM and TEM using the modified thicarbohydrazide procedure of Malich and Wilson, cryofractured, and critical point dried (CPD). Some samples were mechanically fractured after CPD.

Three-Dimensional Subcellular Organization of Hepatocytes in Intact Liver: Simultaneous Visualization of Cytoskeletal and Membrane Markers by Confocal Microscopy

1996 ◽  
Vol 54 ◽  
pp. 288-289
Author(s):  
Greg V. Martin ◽  
Ann L. Hubbard
Keyword(s):  
Three Dimensional ◽  
Integral Membrane Proteins ◽  
Polarized Secretion ◽  
Microscope Images ◽  
Computer Aided ◽  
Intracellular Organelles ◽  
Cytoskeletal Elements ◽  
Simultaneous Visualization

The microtubule (MT) cytoskeleton is necessary for many of the polarized functions of hepatocytes. Among the functions dependent on the MT-based cytoskeleton are polarized secretion of proteins, delivery of endocytosed material to lysosomes, and transcytosis of integral plasma membrane (PM) proteins. Although microtubules have been shown to be crucial to the establishment and maintenance of functional and structural polarization in the hepatocyte, little is known about the architecture of the hepatocyte MT cytoskeleton in vivo, particularly with regard to its relationship to PM domains and membranous organelles. Using an in situ extraction technique that preserves both microtubules and cellular membranes, we have developed a protocol for immunofluorescent co-localization of cytoskeletal elements and integral membrane proteins within 20 µm cryosections of fixed rat liver. Computer-aided 3D reconstruction of multi-spectral confocal microscope images was used to visualize the spatial relationships among the MT cytoskeleton, PM domains and intracellular organelles.

scholarly journals Back Cover: In Situ Observation of Non‐Classical 2‐Norbornyl Cation in Confined Zeolites at Ambient Temperature (Angew. Chem. Int. Ed. 9/2021)

2021 ◽  
Vol 60 (9) ◽  
pp. 4952-4952
Author(s):  
Xiaomin Tang ◽  
Wei Chen ◽  
Xianfeng Yi ◽  
Zhiqiang Liu ◽  
Yao Xiao ◽  
...  
Keyword(s):  
Ambient Temperature ◽  
In Situ Observation ◽  
Back Cover

EFFECTIVENESS OF ANHYDROUS AMMONIA AS A PRESERVATIVE FOR HIGH-MOISTURE ALFALFA HAY IN LARGE ROUND BALES

1986 ◽  
Vol 66 (3) ◽  
pp. 743-753 ◽  
Author(s):  
A. S. ATWAL ◽  
L. C. HESLOP ◽  
K. LIEVERS
Keyword(s):  
Ambient Temperature ◽  
Insoluble Fraction ◽  
Reference Points ◽  
Control Treatment ◽  
High Moisture ◽  
Total N ◽  
Heat Damage ◽  
Anhydrous Ammonia ◽  
Alfalfa Hay ◽  
Large Round

Two experiments were conducted in sequence to determine the effectiveness of anhydrous ammonia (AA) as a preservative of alfalfa hay stored as large round bales (LRB). In the the first experiment application of 3% AA (wt/wt) to alfalfa hay baled at about 23% moisture-content (MC) increased the temperature markedly above the control treatment and resulted in a significantly (P < 0.05) higher acid-detergent-insoluble nitrogen and acid-detergent lignin. In the second experiment application of about 1% AA slowly (over 48 h) to LRB of alfalfa hay packaged at about 30% and > 35% MC, significantly (P < 0.05) reduced the cumulative degree-days above all reference points from 35 to 65 °C. Ammoniation completely eliminated dry matter losses in storage which were highest (8.3%) for 33% MC control hay. High moisture control hay (33% MC) suffered severe heat damage with 33% of total N being in the acid-detergent-insoluble fraction as compared to less than 10% for medium-moisture (26% MC) control and even lower values for ammoniated hay. Digestibility of crude protein and energy was significantly (P < 0.05) improved by ammoniation of medium-moisture (about 30% in-to-storage) alfalfa hay. When the ammonia-treated hay was uncovered in spring, coarsely ground and stored in a hay wagon the high-moisture-ammoniated hay (> 35% MC) became moldy within 4 wk, even when the ambient temperature was about 6 °C, whereas medium-moisture-ammoniated hay (about 30% MC) showed some deterioration after 7 wk as the ambient temperature increased to about 12 °C. Key words: Ammonia, alfalfa hay, digestibility, heat damage, high-moisture hay, large bales

The Membrane Skeleton of Pseudomicrothorax

1991 ◽  
Vol 100 (4) ◽  
pp. 707-715 ◽  
Author(s):  
IRM HUTTENLAUCH ◽  
ROBERT K. PECK
Keyword(s):  
Spatial Organization ◽  
Membrane Skeleton ◽  
Basal Bodies ◽  
Structural Elements ◽  
Or Groups ◽  
Positive Immunoreactivity ◽  
Cortical Membranes ◽  
Cytoskeletal Elements

The membrane skeleton, or epiplasm, is part of the structurally complex ciliate cortex. It is thought to have skeletal functions concerning the spatial organization of cortical elements such as the basal bodies. Here we report the biochemical and immunological characterization of some components of the purified epiplasm of Pseudomicrothorax dubius. The epiplasm proteins consist of two quantitatively major groups of proteins, one of 76–80x103Mr, the other of 11–13x103Mr, which appear to be the principal structural elements of the epiplasm, and a series of minor components of 62–18x103Mr. Based upon lectin labeling and glycosidase treatment, some of the latter have been identified as glycoproteins. Using affinity-purified antibodies specific for individual glycoproteins or groups of glycoproteins, we were able to localize them in situ by immunoelectron microscopical methods. This in situ localization demonstrates that the glycosylated epitopes, unlike the glycoresidues of membrane proteins, are distributed throughout the entire epiplasmic layer rather than being restricted to regions adjacent to the cortical membranes. Thus, these proteins represent glycosylated, cytoskeletal elements. At least one of these glycoproteins (Mr 62x103) shows positive immunoreactivity with a monoclonal antibody (Pruss anti-IFA) recognizing most intermediate filament (IF) proteins, indicating that IF proteins might be present in protozoan cytoskeletons.

The cytoskeletal elements of human retinal pigment epithelium: in vitro and in vivo

1988 ◽  
Vol 91 (2) ◽  
pp. 303-312
Author(s):  
N.M. McKechnie ◽  
M. Boulton ◽  
H.L. Robey ◽  
F.J. Savage ◽  
I. Grierson
Keyword(s):  
Retinal Pigment Epithelium ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Cytokeratin 18 ◽  
Rpe Cells ◽  
Human Retinal Pigment Epithelium ◽  
Cytoskeletal Elements

The cytoskeletal elements of normal (in situ) and cultured human retinal pigment epithelium (RPE) were studied by a variety of immunocytochemical techniques. Primary antibodies to vimentin and cytokeratins were used. Positive immunoreactivity for vimentin was obtained with in situ and cultured material. The pattern of reactivity obtained with antisera and monoclonals to cytokeratins was more complex. Cytokeratin immunoreactivity could be demonstrated in situ and in cultured cells. The pattern of cytokeratin expression was similar to that of simple or glandular epithelia. A monoclonal antibody that specifically recognizes cytokeratin 18 identified a population of cultured RPE cells that had particularly well-defined filamentous networks within their cytoplasm. Freshly isolated RPE was cytokeratin 18 negative by immunofluorescence, but upon culture cytokeratin 18 positive cells were identifiable. Cytokeratin 18 positive cells were identified in all RPE cultures (other than early primaries), regardless of passage number, age or sex of the donor. In post-confluent cultures cytokeratin 18 cells were identified growing over cytokeratin 18 negative cells, suggesting an association of cytokeratin 18 immunoreactivity with cell proliferation. Immunofluorescence studies of retinal scar tissue from two individuals revealed the presence of numerous cytokeratin 18 positive cells. These findings indicate that RPE cells can be identified by their cytokeratin immunoreactivity and that the overt expression of cytokeratin 18 may be associated with proliferation of human RPE both in vitro and in vivo.

Protease Inhibitors Formed In Situ from Copper and Tridentate Chelates: A Generalized Approach towards Metal-Based Pharmaceuticals

ChemBioChem ◽  
2002 ◽  
Vol 3 (11) ◽  
pp. 1141-1143 ◽  
Author(s):  
Christopher J. Brinkerhoff ◽  
Paul Podsiadlo ◽  
Tomoko Komiyama ◽  
Robert S. Fuller ◽  
Ofer Blum
Keyword(s):  
Protease Inhibitors

Preliminary Experimental Study of Warm Ultrasonic Impact-assisted Laser Metal Deposition

2021 ◽  
pp. 1-15
Author(s):  
Hanyu Song ◽  
Minglang Li ◽  
Muxuan Wang ◽  
Benxin Wu ◽  
Ze Liu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Experimental Study ◽  
Solid Material ◽  
Metal Deposition ◽  
Laser Metal Deposition ◽  
Ultrasonic Impact Treatment ◽  
Post Process ◽  
Underlying Mechanisms ◽  
Manufacturing Time

Abstract A preliminary experimental study on “warm ultrasonic impact-assisted laser metal deposition” (WUI-LMD) is reported, and such a study is rare in literatures to the authors' knowledge. In WUI-LMD, an ultrasonic impact treatment (UIT) tip is placed near laser spot for in-situ treatment of laser-deposited warm solid material, and the UIT and LMD processes proceed simultaneously. Under the conditions investigated, it is found that in-situ UIT during WUI-LMD can be much more effective in reducing porosity than a post-process UIT. Possible underlying mechanisms are analyzed. WUI-LMD has a great potential to reduce defects and improve mechanical properties without increasing manufacturing time.

Study on the Properties of Aerodynamic Reference Sound Sources

2019 ◽  
Vol 105 (6) ◽  
pp. 960-969 ◽  
Author(s):  
Spyros Brezas ◽  
Volker Wittstock
Keyword(s):  
Ambient Temperature ◽  
Atmospheric Pressure ◽  
Rotation Speed ◽  
Near Field ◽  
Sound Power ◽  
Sound Sources ◽  
The Core ◽  
In Situ Conditions ◽  
Calibration Condition

Towards the establishment of traceability in sound power in airborne sound, the present study focuses on the dissemination procedure. Aerodynamic reference sound sources were studied as potential transfer standards. Initially, the sources were examined in the up-to-present requirements. The core of the study is the correction required for the transition from calibration to in situ conditions. The influence of atmospheric pressure, ambient temperature and fan rotation speed was investigated and the corresponding correction was determined. A comparison to an existing correction was also performed. Near field effects were another part of the study. The related uncertainty was estimated in a transparent approach. The dependency of the uncertainty on the in situ and calibration condition values is also presented.

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