Functional Studies of the Extrahepatic Biliary System in the Dog by Use of a Controlled Biliary Fistula

An interesting feature of the goldfish liver is the morphology of the hepatic plate, which is always formed by a two-cell layer of hepatocytes. Hepatic plates of the goldfish liver contain an infrequently seen second type of cell, in the centers of plates between two hepatocytes. A TEH study by Yamamoto (1) demonstrated ultrastructural differences between hepatocytes and centrally located cells in hepatic plates; the latter were classified as ductule cells of the biliary system. None of the previous studies clearly showed a three-dimensional organization of the two cell types described. In the present investigation we utilize SEM to elucidate the arrangement of hepatocytes and bile ductular cells in intralobular plates of goldfish liver.Livers from young goldfish (Carassius auratus), about 6-10 cm, fed commercial fish food were used for this study. Hepatic samples were fixed in 4% buffered paraformaldehyde, cut into pieces, fractured, osmicated, CPD, mounted Au-Pd coated, and viewed by SEM at 17-20 kV. Our observations were confined to the ultrastructure of biliary passages within intralobular plates, ductule cells, and hepatocytes.

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The low-resolution 3D-structure of porin, a channel-forming protein in E. coliouter membranes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075932 ◽

1983 ◽

Vol 41 ◽

pp. 440-441

Author(s):

A. Engel ◽

D.L. Dorset ◽

A. Massalski ◽

J.P. Rosenbusch

Keyword(s):

Crystal Packing ◽

3D Structure ◽

Gram Negative Bacteria ◽

Protein Ratio ◽

Crystal Forms ◽

Large Molecules ◽

Functional Studies ◽

Voltage Dependent ◽

Planar Membranes ◽

Hexagonal Arrays

Porins represent a group of channel forming proteins that facilitate diffusion of small solutes across the outer membrane of Gram-negative bacteria, while excluding large molecules (>650 Da). Planar membranes reconstituted from purified matrix porin (OmpF protein) trimers and phospholipids have allowed quantitative functional studies of the voltage-dependent channels and revealed concerted activation of triplets. Under the same reconstitution conditions but using high protein concentrations porin aggregated to 2D lattices suitable for electron microscopy and image processing. Depending on the lipid-to- protein ratio three different crystal packing arrangements were observed: a large (a = 93 Å) and a small (a = 79 Å) hexagonal and a rectangular (a = 79 Å b = 139 Å) form with p3 symmetry for the hexagonal arrays. In all crystal forms distinct stain filled triplet indentations could be seen and were found to be morphologically identical within a resolution of (22 Å). It is tempting to correlate stain triplets with triple channels, but the proof of this hypothesis requires an analysis of the structure in 3 dimensions.

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Ionic homeostasis and subcellular element compartmentation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010013434x ◽

1990 ◽

Vol 48 (2) ◽

pp. 150-151

Author(s):

Ann LeFurgey ◽

Peter Ingram ◽

J.J. Blum ◽

M.C. Carney ◽

L.A. Hawkey ◽

...

Keyword(s):

Leishmania Major ◽

Ionic Homeostasis ◽

X Ray ◽

Functional Studies ◽

Cell Compartments ◽

X Ray Imaging ◽

Resolution Electron ◽

Multiple Cell ◽

Role Of Zn

Subcellular compartments commonly identified and analyzed by high resolution electron probe x-ray microanalysis (EPXMA) include mitochondria, cytoplasm and endoplasmic or sarcoplasmic reticulum. These organelles and cell regions are of primary importance in regulation of cell ionic homeostasis. Correlative structural-functional studies, based on the static probe method of EPXMA combined with biochemical and electrophysiological techniques, have focused on the role of these organelles, for example, in maintaining cell calcium homeostasis or in control of excitation-contraction coupling. New methods of real time quantitative x-ray imaging permit simultaneous examination of multiple cell compartments, especially those areas for which both membrane transport properties and element content are less well defined, e.g. nuclei including euchromatin and heterochromatin, lysosomes, mucous granules, storage vacuoles, microvilli. Investigations currently in progress have examined the role of Zn-containing polyphosphate vacuoles in the metabolism of Leishmania major, the distribution of Na, K, S and other elements during anoxia in kidney cell nuclel and lysosomes; the content and distribution of S and Ca in mucous granules of cystic fibrosis (CF) nasal epithelia; the uptake of cationic probes by mltochondria in cultured heart ceils; and the junctional sarcoplasmic retlculum (JSR) in frog skeletal muscle.

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Phytochemical and functional studies on the roots of Armoracia rusticana

10.1055/s-0037-1608402 ◽

2017 ◽

Author(s):

E Jimenez Negro ◽

J Sendker ◽

B Scharf ◽

M Kleinwächter ◽

B Lipowicz ◽

...

Keyword(s):

Armoracia Rusticana ◽

Functional Studies

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A HOME-MADE BILIARY SENGSTAKEN TUBE AS A TEMPORIZING STRATEGY FOR MASSIVE BLEEDING SECONDARY TO ARTERIO-BILIARY FISTULA (ABF)

10.1055/s-0038-1637279 ◽

2018 ◽

Author(s):

M Cimavilla-Roman ◽

R Torres-Yuste ◽

A Carbajo-Lopez ◽

R Sanchez-Ocana ◽

M de Benito-Sanz ◽

...

Keyword(s):

Massive Bleeding ◽

Biliary Fistula

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Heparin Excretion in Intact and Hepatectomized Rats

Thrombosis and Haemostasis ◽

10.1055/s-0038-1650152 ◽

1981 ◽

Vol 45 (02) ◽

pp. 146-149

Author(s):

Ray Losito ◽

Harry Gattiker ◽

Ginette Bilodeau

Keyword(s):

Column Chromatography ◽

Normal Values ◽

Anticoagulant Activity ◽

Biliary Fistula ◽

Kinetics Of ◽

Intact Rats

SummaryMetabolism and kinetics of 3H-heparin were compared in intact and hepatectomized rats. Rats were divided into three groups: 1) intact rats with biliary fistulas and cystostomies 2) intact rats with only cystostomies and 3) hepatectomized rats with cystostomies. Radioactivity in blood, bile and urine besides anticoagulant activity in blood and urine were examined. In addition, column chromatography of urine was used to isolate possible metabolites. Seventy percent and 80% of the radioactive dose was found in the urine of intact rats at 24 hr and 48 hr. Close to 5% of the radioactivity was found in bile or rats with a biliary fistula after 48 hr. The APTT declined to near normal values at 1 hr whether rats had a biliary fistula or not. In contrast, only 25 % of the radioactivity could be excreted into the urine of hepatectomized rats in 24 hr; the APTT did not decline as fast and at 5 hr, it was still 100 seconds. Only one radioactive component could be isolated on chromatography from all urines of these animals and appears to be similar to the original heparin. Thus, the liver has an important role to play in regulating the anticoagulant effects and excretion of heparin.

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Functional Characterization of a Variant Factor XII (F XII Locarno) in a Cross Reacting Material Positive F XII Deficient Plasma

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648416 ◽

1992 ◽

Vol 67 (02) ◽

pp. 219-225 ◽

Cited By ~ 6

Author(s):

Walter A Wuillemin ◽

Miha Furlan ◽

Hans Stricker ◽

Bernhard Lämmle

Keyword(s):

Dextran Sulfate ◽

Functional Characterization ◽

Healthy Woman ◽

Chain Molecule ◽

Plasma Kallikrein ◽

Factor Xii ◽

Single Chain ◽

Sulfate Adsorption ◽

Prolonged Incubation ◽

Functional Studies

SummaryThe plasma of a healthy woman was found to contain half normal factor XII (FXII) antigen level (0.46 U/ml) without any FXII clotting activity (<0.01 U/ml). The variant FXII in this plasma, denoted as FXII Locarno, was partially characterized by immunological and functional studies on the proposita’s plasma. FXII Locarno is a single chain molecule with the same size (M r = 80 kDa) as normal FXII. Isoelectric focusing suggested an excess of negative charge in the variant FXII as compared to normal FXII. In contrast to FXII in normal plasma, FXII Locarno was not proteolytically cleaved upon prolonged incubation of proposita’s plasma with dextran sulfate. Adsorption to kaolin was similar for both, abnormal and normal FXII. Incubation of the proposita’s plasma with dextran sulfate and exogenous plasma kallikrein showed normal cleavage of FXII Locarno outside of the tentative disulfide loop Cys340-Cys467, but only partial cleavage within this disulfide loop. Furthermore, plasma kallikrein-cleaved abnormal FXII showed neither amidolytic activity nor proteolytic activity against factor XI and plasma prekallikrein.These results suggest a structural alteration of FXII Locarno, affecting the plasma kallikrein cleavage site Arg353-Val354 and thus formation of activated FXII (a-FXIIa).

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