Cytochemical localization of acid mucosubstances within intestinal tissue stages ofEimeria acervulina andE. necatrix

1972 ◽  
Vol 4 (1) ◽  
pp. 9-24 ◽  
Author(s):  
E. Michael ◽  
R. D. Hodges
1969 ◽  
Vol 17 (1) ◽  
pp. 36-46 ◽  
Author(s):  
WILLIAM J. DOUGHERTY

Skeletal muscles of rabbits, chickens, frogs and fishes were studied by bright field, phase contrast and polarization microscopy after treatment with: (1) Alcian Blue, pH 2.5, (2) Alcian Blue, pH 1.0, (3) low iron diamine, (4) high iron diamine, (5) dialyzed iron, pH 2.0, and (6) colloidal iron, pH 1.5. A prominent aspect of each of the muscles studied was transverse muscle bands which stained with Alcian Blue at pH 2.5, low iron diamine and dialyzed and colloidal iron reagents. Staining of transverse bands was not very intense with these reagents, suggesting that the materials demonstrated occurred in relatively low concentrations. Staining of transverse bands in chicken, frog and fish muscles was observed also after treatment with Alcian Blue at pH 1.0 or with high iron diamine. Staining of rabbit muscle with Alcian Blue at pH 1.0 or with high iron diamine was not detectable even after the most effective fixatives employed in this study, viz., Carony's fixative or buffered HgCl2. Phase contrast and polarization microscopy indicated that the transverse bands stained by the reagents employed corresponded to the I bands in agreement with previous electron cytochemical studies of skeletal muscles treated with dialyzed iron at controlled pH. Methylation for 4 hr at 60°C prevented I band staining with Alcian Blue and dialyzed iron in each of the muscles studied. Treatment of muscle sections with Vibrio cholerae neuraminidase, testicular hyaluronidase or ribonuclease under optimal conditions did not prevent Alcian Blue staining of I bands. Trypsin treatment of muscle sections did not prevent I band staining except when digestion was prolonged to the point that muscle striations were no longer recognizable. Saponification prior to hyaluronidase treatment reduced I band staining in each of the muscles studied. Saponification alone and saponification prior to neuraminidase digestion left I band alcianophilia intact. It was concluded that myofibrillar I bands of rabbit, chicken, frog and fish skeletal muscles contain acid mucosubstances. It was suggested that in each of these organisms an esterified, hyaluronic acid-like molecule is present within the I bands. Sulfated mucosaccharides occur as additional components in the I bands of fish, chicken and frog skeletal muscles; sulfated mucosaccharides apparently are not present in rabbit muscle I bands. Available evidence indicates that sialomucins are not present in the myofibrils of the organisms studied. The possible functional significance of I band acid mucosubstances in vertebrate skeletal muscles was discussed.


Author(s):  
W. A. Shannon ◽  
M. A. Matlib

Numerous studies have dealt with the cytochemical localization of cytochrome oxidase via cytochrome c. More recent studies have dealt with indicating initial foci of this reaction by altering incubation pH (1) or postosmication procedure (2,3). The following study is an attempt to locate such foci by altering membrane permeability. It is thought that such alterations within the limits of maintaining morphological integrity of the membranes will ease the entry of exogenous substrates resulting in a much quicker oxidation and subsequently a more precise definition of the oxidative reaction.The diaminobenzidine (DAB) method of Seligman et al. (4) was used. Minced pieces of rat liver were incubated for 1 hr following toluene treatment (5,6). Experimental variations consisted of incubating fixed or unfixed tissues treated with toluene and unfixed tissues treated with toluene and subsequently fixed.


Author(s):  
Judith A. Murphy ◽  
Mary R. Thompson ◽  
A.J. Pappelis

In an attempt to identify polysaccharide components in thin sections of D. maydis, procedures were employed such that a PAS localization could be carried out. Three different fixatives were evaluated ie. glutaraldehyde, formaldehyde and paraformaldehyde. These were used in conjunction with periodic acid (PA), thiosemicarbazide(TSC), and osmium tetroxide(Os) to localize polysaccharides in V. maydis using a pre-embedded reaction procedure. Polysaccharide localization is based on the oxidation of vic-glycol groups by PA, and the binding of TSC as a selective reaction center for the formation of osmium black. The reaction product is sufficiently electron opaque, insoluble in lipids, not altered when tissue is embedded, and has a fine amorphous character.


2009 ◽  
Vol 00 (00) ◽  
pp. 090810023429058-9
Author(s):  
Juan Cheng ◽  
Zheng Hong Wu ◽  
Qineng Neng Ping ◽  
Bogang Wang ◽  
Junjun Lu

2020 ◽  
Vol 10 ◽  
Author(s):  
Bianca Peterson ◽  
Henrico Heystek ◽  
Josias H. Hamman ◽  
Johan D. Steyn

Background:: Knowledge of the permeation characteristics of new chemical entities across biological membranes is essential to drug research and development. Transport medium composition may affect the absorption of compounds during in vitro drug transport testing. To preserve the predictive values of screening tests, the possible influence of transport media on the solubility of model drugs, and on the activities of tight junctions and efflux transporter proteins (e.g. P-glycoprotein) must be known. Objective:: The aim of this study was to compare the impact of different transport media on the bi-directional transport of standard compounds, selected from the four classes of the Biopharmaceutical Classification System (BCS), across excised pig intestinal tissue. Methods:: The Sweetana-Grass diffusion apparatus was used for the transport studies. Krebs-Ringer bicarbonate (KRB) buffer and simulated intestinal fluids in the fed (FeSSIF) and fasted (FaSSIF) states were used as the three transport media, while the chosen compounds were abacavir (BCS class 1), dapsone (BCS class 2), lamivudine (BCS class 3) and furosemide (BCS class 4). Results:: Abacavir exhibited lower permeability in both the simulated intestinal fluids than in the KRB buffer. Dapsone showed similar permeability in all media. Lamivudine exhibited lower permeability in FaSSIF than in the other two media. Furosemide exhibited improved transport with pronounced efflux in FaSSIF. Conclusion:: Different permeation behaviors were observed for the selected drugs in the respective media, which may have resulted from their different physico-chemical properties, as well as from the effects that dissimilar transport media components had on excised pig intestinal tissue.


2021 ◽  
Vol 27 (Supplement_1) ◽  
pp. S34-S34
Author(s):  
Ren Mao ◽  
Genevieve Doyon ◽  
Ilyssa Gordon ◽  
Jiannan Li ◽  
Sinan Lin ◽  
...  

Abstract Background and Aims Creeping fat, the wrapping of mesenteric fat around the bowel wall, is a typical feature of Crohn’s disease, and is associated with stricture formation and bowel obstruction. How creeping fat forms is unknown, and we interrogated potential mechanisms using novel intestinal tissue and cell interaction systems. Methods Tissues from normal, ulcerative colitis, non-strictured and strictured Crohn’s disease intestinal specimens were obtained. Fresh and decellularized tissue, mesenteric fat explants, primary human adipocytes, pre-adipocytes, muscularis propria cells, and native extracellular matrix were used in multiple ex vivo and in vitro systems involving cell growth, differentiation and migration, proteomics, and integrin expression. Results Crohn’s disease muscularis propria cells produced an extracellular matrix scaffold which is in direct spatial and functional contact with the immediately overlaid creeping fat. The scaffold contained multiple proteins, but only fibronectin production was singularly upregulated by TGF-b1. The muscle cell-derived matrix triggered migration of pre-adipocytes out of mesenteric fat, fibronectin being the dominant factor responsible for their migration. Blockade of α5β1 on the pre-adipocyte surface inhibited their migration out of mesenteric fat and on 3D decellularized intestinal tissue extracellular matrix. Conclusion Crohn’s disease creeping fat appears to result from the migration of pre-adipocytes out of mesenteric fat and differentiation into adipocytes in response to an increased production of fibronectin by activated muscularis propria cells. These new mechanistic insights may lead to novel approaches for prevention of creeping fat-associated stricture formation.


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