Interpretation of Coronary Vascular Perfusion

Author(s):  
H. Frederick Frasch ◽  
J. Yasha Kresh ◽  
Abraham Noordergraaf
Keyword(s):  
Author(s):  
Peter M. Andrews

Although there have been a number of recent scanning electron microscopic reports on the renal glomerulus, the advantages of scanning electron microscopy have not yet been applied to a systematic study of the uriniferous tubules. In the present investigation, scanning electron microscopy was used to study the ultrastructural morphology of the proximal, distal, thin loop, and collecting tubules. Material for observation was taken from rat kidneys which were fixed by vascular perfusion, sectioned by either cutting or fracturing technigues, and critically point dried.The brush border characterising proximal tubules is first detected on the luminal surface of Bowman's capsule adjacent to the urinary pole orifice. In this region one frequently finds irregular microvilli characterized by broad and flattened bases with occasional bulbous structures protruding from their surfaces.


Author(s):  
R. P. Becker ◽  
J. J. Wolosewick ◽  
J. Ross-Stanton

Methodology has been introduced recently which allows transmission and scanning electron microscopy of cell fine structure in semi-thin sections unencumbered by an embedding medium. Images obtained from these “resinless” sections show a three-dimensional lattice of microtrabeculfee contiguous with cytoskeletal structures and membrane-bounded cell organelles. Visualization of these structures, especially of the matiiDra-nous components, can be facilitated by employing tannic acid in the fixation step and dessicator drying, as reported here.Albino rats were fixed by vascular perfusion with 2% glutaraldehyde or 1.5% depolymerized paraformaldehyde plus 2.5% glutaraldehyde in 0.1M sodium cacodylate (pH 7.4). Tissues were removed and minced in the fixative and stored overnight in fixative containing 4% tannic acid. The tissues were rinsed in buffer (0.2M cacodylate), exposed to 1% buffered osmium tetroxide, dehydrated in ethyl alcohol, and embedded in pure polyethylene glycol-6000 (PEG). Sections were cut on glass knives with a Sorvall MT-1 microtome and mounted onto poly-L-lysine, formvar-carbon coated grids while submerged in a solution of 95% ethanol containing 5% PEG.


Author(s):  
A.S. Lossinsky ◽  
M.J. Song

Previous studies have suggested the usefulness of high-voltage electron microscopy (HVEM) for investigating blood-bram barrier (BBB) injury and the mechanism of inflammatory-cell (IC) attachment. These studies indicated that, in evaluating standard conventional thin sections, one might miss cellular attachment sites of ICs in their process of attaching to the luminal endothelial cell (EC) surface of cerebral blood vessels. Our current studies in animals subjected to autoimmune disease suggest that HVEM may be useful in localizing precise receptor sites involved in early IC attachment.Experimental autoimmune encephalomyelitis (EAE) was induced in mice and rats according to standard procedures. Tissue samples from cerebellum, thalamus or spinal cords were embedded in plastic following vascular perfusion with buffered aldehyde. Thick (0.5-0.7 μm) sections were cut on glass knives and collected on Formvar-coated slot grids stained with uranylacetate and lead citrate and examined with the AEI EM7 1.2 MV HVEM in Albany, NY at 1000 kV.


1997 ◽  
Vol 78 (05) ◽  
pp. 1408-1414 ◽  
Author(s):  
Frank Roesken ◽  
Martin Ruecker ◽  
Brigitte Vollmar ◽  
Nicole Boeckel ◽  
Eberhard Morgenstern ◽  
...  

SummaryThe alteration of rheological blood properties as well as deterioration of vascular perfusion conditions and cell-cell interactions are major determinants of thrombus formation. Herein, we present an experimental model which allows for quantitative in vivo microscopic analysis of these determinants during both thrombus formation and vascular recanalisation. The model does not require surgical preparation procedures, and enables for repeated analysis of identical microvessels over time periods of days or months, respectively. After i.v. administration of FITC-dextran thrombus formation was induced photochemically by light exposure to individual arterioles and venules of the ear of ten anaesthetised hairless mice. In venules, epiillumination induced rapid thrombus formation with first platelet deposition after 0.59 ± 0.04 min and complete vessel occlusion within 7.48 ±1.31 min. After a 24-h time period, 75% of the thrombosed venules were found recanalised. Marked leukocyte-endothelial cell interaction in those venules indicated persistent endothelial cell activation and/or injury, even after an observation period of 7 days. In arterioles, epi-illumination provoked vasomotion, while thrombus formation was significantly (p <0.05) delayed with first platelet deposition after 2.32 ± 0.22 min and complete vessel occlusion within 20.07 ±3.84 min. Strikingly, only one of the investigated arterioles was found recanalised after 24 h, which, however, did not show leukocyte-endothelial cell interaction. Heparin (300 U/kg, i.v.) effectively counteracted the process of thrombus formation in this model, including both first platelet deposition and vessel occlusion. We conclude that the model of the ear of the hairless mouse allows for distinct in vivo analysis of arteriolar and venular thrombus formation/ recanalisation, and, thus, represents an interesting tool for the study of novel antithrombotic and thrombolytic strategies, respectively.


Author(s):  
Roman Grothausmann ◽  
Jonas Labode ◽  
Pablo Hernandez-Cerdan ◽  
David Haberthür ◽  
Ruslan Hlushchuk ◽  
...  

AbstractVarious lung diseases, including pulmonary hypertension, chronic obstructive pulmonary disease or bronchopulmonary dysplasia, are associated with structural and architectural alterations of the pulmonary vasculature. The light microscopic (LM) analysis of the blood vessels is limited by the fact that it is impossible to identify which generation of the arterial tree an arterial profile within a LM microscopic section belongs to. Therefore, we established a workflow that allows for the generation-specific quantitative (stereological) analysis of pulmonary blood vessels. A whole left rabbit lung was fixed by vascular perfusion, embedded in glycol methacrylate and imaged by micro-computed tomography (µCT). The lung was then exhaustively sectioned and 20 consecutive sections were collected every 100 µm to obtain a systematic uniform random sample of the whole lung. The digital processing involved segmentation of the arterial tree, generation analysis, registration of LM sections with the µCT data as well as registration of the segmentation and the LM images. The present study demonstrates that it is feasible to identify arterial profiles according to their generation based on a generation-specific color code. Stereological analysis for the first three arterial generations of the monopodial branching of the vasculature included volume fraction, total volume, lumen-to-wall ratio and wall thickness for each arterial generation. In conclusion, the correlative image analysis of µCT and LM-based datasets is an innovative method to assess the pulmonary vasculature quantitatively.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ping Li ◽  
Lin Jin ◽  
Lan Feng ◽  
Yingchun Wang ◽  
Rong Yang

AbstractTo investigate the feasibility of using ICAM-1-targeted nano ultrasonic contrast to evaluate the degree of inflammatory injury at different stages in the abdominal aorta of rabbits with atherosclerosis (AS). Twenty-five experimental rabbits were assigned to five groups: the control group (A); the week-4 after modeling group (B); the week-8 after modeling group (C); the week-12 after modeling group (D); the week-16 after modeling group (E). All groups were given 2D ultrasonography, conventional ultrasonic contrast (SonoVue), and ICAM-1-targeted nano ultrasonic contrast, respectively. Signal intensity of vascular perfusion was evaluated. Signal intensity of ICAM-1-targeted nano ultrasonic contrast was substantially enhanced and prolonged in the vascular wall of the abdominal bubble aorta increased in B, C, D, and E groups (all P < 0.05). A positive linear correlation between intensity and the expression of ICAM-1 (r = 0.895, P < 0.001). The intensity of outer membrane was enhanced from week 4 to week 12, and both the intima-media membrane and outer membrane were enhanced with double-layer parallel echo at week 16, which was in line with the progression of atherosclerotic plaque inflammatory injury. ICAM-1-targeted nano contrast agent would be possibly a novel non-invasive molecular imaging method for plaque inflammatory injury and site high expression of specific adhesion molecules in early atherosclerotic lesions.


Stroke ◽  
2020 ◽  
Vol 51 (8) ◽  
pp. 2480-2487
Author(s):  
Salvatore Rudilosso ◽  
Alejandro Rodríguez ◽  
Sergio Amaro ◽  
Víctor Obach ◽  
Arturo Renú ◽  
...  

Background and Purpose: Acute onset aphasia may be due to stroke but also to other causes, which are commonly referred to as stroke mimics. We hypothesized that, in patients with acute isolated aphasia, distinct brain perfusion patterns are related to the cause and the clinical outcome. Herein, we analyzed the prognostic yield and the diagnostic usefulness of computed tomography perfusion (CTP) in patients with acute isolated aphasia. Methods: From a single-center registry, we selected a cohort of 154 patients presenting with acute isolated aphasia who had a whole-brain CTP study available. We collected the main clinical and radiological data. We categorized brain perfusion studies on CTP into vascular and nonvascular perfusion patterns and the cause of aphasia as ischemic stroke, transient ischemic attack, stroke mimic, and undetermined cause. The primary clinical outcome was the persistence of aphasia at discharge. We analyzed the sensitivity, specificity, positive and negative predictive values of perfusion patterns to predict complete clinical recovery and ischemic stroke on follow-up imaging. Results: The cause of aphasia was an ischemic stroke in 58 patients (38%), transient ischemic attack in 3 (2%), stroke mimic in 68 (44%), and undetermined in 25 (16%). CTP showed vascular and nonvascular perfusion pattern in 62 (40%) and 92 (60%) patients, respectively. Overall, complete recovery occurred in 116 patients (75%). A nonvascular perfusion pattern predicted complete recovery (sensitivity 75.9%, specificity 89.5%, positive predictive value 95.7%, and negative predictive value 54.8%), and a vascular perfusion pattern was highly predictive of ischemic stroke (sensitivity 94.8%, specificity 92.7%, positive predictive value 88.7%, and negative predictive value 96.7%). The 3 patients with ischemic stroke without a vascular perfusion pattern fully recovered at discharge. Conclusions: CTP has prognostic value in the workup of patients with acute isolated aphasia. A nonvascular pattern is associated with higher odds of full recovery and may prompt the search for alternative causes of the symptoms.


Spine ◽  
1996 ◽  
Vol 21 (14) ◽  
pp. 1657-1660 ◽  
Author(s):  
Jean-Yves Maigne ◽  
Claude Treuil ◽  
Gilles Chatellier

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