scholarly journals I. On the minute structure of the lung of the newt with especial reference to its nervous apparatus

1881 ◽  
Vol 32 (212-215) ◽  
pp. 37-38 ◽  

The lungs of the newt and triton are essentially simple sacs without any septa projecting into their interior, so that they are remarkably well suited for microscopic examination. They are covered externally by a layer of endothelium, but there are no stomata to be found between the endothelial cells. Under this is a small quantity of areolar tissue containing a plexus of yellow elastic fibres, with the long axis of the meshes arranged in the long axis of the lung-sac. Under this is a layer of non-striped muscular fibres, which forms a complete investment for the lung. These muscular fibres are disposed circularly. They present the same structure as similar cells in the mesentery of the newt. Each cell contains an intra-nuclear and intra­cellular plexus of fibrils.

2019 ◽  
Vol 5 (6) ◽  
pp. 424-431
Author(s):  
Hillary C. Stiefel ◽  
John D. Ng ◽  
David J. Wilson ◽  
Daniel M. Albert

Purpose: To report a case of orbital cellular epithelioid hemangioma (EH) in which FOSB and CAMTA1 immunostains were used to detect a cytogenetic rearrangement as an adjunctive tool in diagnosis. Methods: Case report. Results: A patient with a history of prior ligation of a presumed orbital varix presented with recurrent proptosis. Imaging revealed a highly vascular right orbital mass. Microscopic examination revealed a circumscribed neoplasm composed of plump epithelioid endothelial cells with copious mildly eosinophilic cytoplasm and relatively uniform vesicular nuclei. To aid in diagnosis, immunostains for FOSB and CAMTA1 were performed to detect corresponding cytogenetic rearrangements. The presence of multifocal nuclear positivity for FOSB, indicating FOSB genetic rearrangement, and negativity for CAMTA1 were considered reassuring features against a diagnosis of a malignant epithelioid hemangioendothelioma (EHE), supporting a diagnosis of benign cellular EH. Conclusions: This case report demonstrates that the use of immunohistochemical stains to detect cytogenetic rearrangements may aid in the distinction between benign EH and malignant EHE. It also reminds providers of the clinical and histopathologic features of this lesion, which occurs rarely in the orbit, and helps clarify the evolving nomenclature surrounding epithelioid hemangioma.


Author(s):  
D. E. Philpott ◽  
A. Takahashi

Two month, eight month and two year old rats were treated with 10 or 20 mg/kg of E. Coli endotoxin I. P. The eight month old rats proved most resistant to the endotoxin. During fixation the aorta, carotid artery, basil arartery of the brain, coronary vessels of the heart, inner surfaces of the heart chambers, heart and skeletal muscle, lung, liver, kidney, spleen, brain, retina, trachae, intestine, salivary gland, adrenal gland and gingiva were treated with ruthenium red or alcian blue to preserve the mucopolysaccharide (MPS) coating. Five, 8 and 24 hrs of endotoxin treatment produced increasingly marked capillary damage, disappearance of the MPS coating, edema, destruction of endothelial cells and damage to the basement membrane in the liver, kidney and lung.


Author(s):  
K. S. McCarty ◽  
R. F. Weave ◽  
L. Kemper ◽  
F. S. Vogel

During the prodromal stages of sporulation in the Basidiomycete, Agaricus bisporus, mitochondria accumulate in the basidial cells, zygotes, in the gill tissues prior to entry of these mitochondria, together with two haploid nuclei and cytoplasmic ribosomes, into the exospores. The mitochondria contain prominent loci of DNA [Fig. 1]. A modified Kleinschmidt spread technique1 has been used to evaluate the DNA strands from purified whole mitochondria released by osmotic shock, mitochondrial DNA purified on CsCl gradients [density = 1.698 gms/cc], and DNA purified on ethidium bromide CsCl gradients. The DNA appeared as linear strands up to 25 u in length and circular forms 2.2-5.2 u in circumference. In specimens prepared by osmotic shock, many strands of DNA are apparently attached to membrane fragments [Fig. 2]. When mitochondria were ruptured in hypotonic sucrose and then fixed in glutaraldehyde, the ribosomes were released for electron microscopic examination.


Author(s):  
C. N. Sun ◽  
J. J. Ghidoni

Endothelial cells in longitudinal and cross sections of aortas from 3 randomly selected “normal” mongrel dogs were studied by electron microscopy. Segments of aorta were distended with cold cacodylate buffered 5% glutaraldehyde for 10 minutes prior to being cut into small, well oriented tissue blocks. After an additional 1-1/2 hour period in glutaraldehyde, the tissue blocks were well rinsed in buffer and post-fixed in OsO4. After dehydration they were embedded in a mixture of Maraglas, D.E.R. 732, and DDSA.Aldehyde fixation preserves the filamentous and tubular structures (300 Å and less) for adequate demonstration and study. The functional significance of filaments and microtubules has been recently discussed by Buckley and Porter; the precise roles of these cytoplasmic components remains problematic. Endothelial cells in canine aortas contained an abundance of both types of structures.


Author(s):  
Waykin Nopanitaya ◽  
Raeford E. Brown ◽  
Joe W. Grisham ◽  
Johnny L. Carson

Mammalian endothelial cells lining hepatic sinusoids have been found to be widely fenestrated. Previous SEM studies (1,2) have noted two general size catagories of fenestrations; large fenestrae were distributed randomly while the small type occurred in groups. These investigations also reported that large fenestrae were more numerous and larger in the endothelial cells at the afferent ends of sinusoids or around the portal areas, whereas small fenestrae were more numerous around the centrilobular portion of the hepatic lobule. It has been further suggested that under some physiologic conditions small fenestrae could fuse and subsequently become the large type, but this is, as yet, unproven.We have used a reproducible experimental model of hypoxia to study the ultrastructural alterations in sinusoidal endothelial fenestrations in order to investigate the origin of occurrence of large fenestrae.


Author(s):  
Veronika Burmeister ◽  
N. Ludvig ◽  
P.C. Jobe

Electron microscopic immunocytochemistry provides an important tool to determine the ultrastructural distribution of various molecules in both normal and pathologic tissues. However, the specific immunostaining may be obscured by artifactual immunoreaction product, misleading the investigator. Previous observations show that shortening the incubation period with the primary antibody from the generally used 12-24 hours to 1 hour substantially reduces the artifactual immunostaining. We now extend this finding by the demonstration of artifact-free ultrastructural localization of the Ca2/calmodulindependent cyclic nucleotide phosphodiesterase (CaM-dependent PDE) immunoreactivity in brain.Anesthetized rats were perfused transcardially with phosphate-buffered saline followed by a fixative containing paraformaldehyde (4%) and glutaraldehyde (0.25%) in PBS. The brains were removed, and 40μm sections were cut with a vibratome. The sections were processed for immunocytochemistry as described by Ludvig et al. Both non-immune rabbit serum and specific CaM-dependent PDE antibodies were used. In both experiments incubations were at one hour and overnight. The immunostained sections were processed for electron microscopic examination.


Author(s):  
D.J.P. Ferguson ◽  
M. Virji ◽  
H. Kayhty ◽  
E.R. Moxon

Haemophilus influenzae is a human pathogen which causes meningitis in children. Systemic H. influenzae infection is largely confined to encapsulated serotype b organisms and is a major cause of meningitis in the U.K. and elsewhere. However, the pathogenesis of the disease is still poorly understood. Studies in the infant rat model, in which intranasal challenge results in bacteraemia, have shown that H. influenzae enters submucosal tissues and disseminates to the blood stream within minutes. The rapidity of these events suggests that H. influenzae penetrates both respiratory epithelial and endothelial barriers with great efficiency. It is not known whether the bacteria penetrate via the intercellular junctions, are translocated within the cells or carried across the cellular barrier in 'trojan horse' fashion within phagocytes. In the present studies, we have challenged cultured human umbilical cord_vein endothelial cells (HUVECs) with both capsulated (b+) and capsule-deficient (b-) isogenic variants of one strain of H. influenzae in order to investigate the interaction between the bacteria and HUVEC and the effect of the capsule.


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