Liver structure

Korpela, H., Kumpulainen, J., Luoma, P.V., Arranto, A.J. and Sotaniemi, E.A. (1985). Decreased serum selenium in alcoholics as related to liver structure and function. Am. J. Clin. Nutr. 42, 147-151. 

Portal hypertension is a consequence of increased resistance to blood flow through the portal vein. Increased resistance is usually due to restructuring of intrahepatic tissue (sinusoidal damage) but may also be caused by presinusoidal damage such as portal vein occlusion from trauma, malignancy, or thrombosis. A third (and the least common) mechanism is outflow obstruction of the hepatic vein. This latter damage is posthepatic, and normal liver structure is maintained. This chapter will focus on portal hypertension caused by intrahepatic damage from cirrhosis. 

Cirrhosis Widespread disruption of normal liver structure by fibrosis and the formation of regenerative nodules that is caused by any of various chronic progressive conditions affecting the liver. 

Guzelian PS. 1985. Clinical evaluation of liver structure and function in humans exposed to halogenated hydrocarbons. Environ Health Perspect 60 159-164. 

Guzelian PS, Vranian G, Boylan J J, et al. 1980. Liver structure and function in patients poisoned with chlordecone (Kepone). Gastroenterology 78 206-213. 

Yarbrough JD, Chambers JE, Robinson KM. 1982. Alterations in liver structure and function resulting from chronic insecticide exposure. In Chambers JE, Yarbrough JD, eds. Effects of chronic exposures to pesticides on animal systems. New York, NY Raven Press, 25-59. 

Studies of liver structure may be carried out using colloidal dispersions labelled with "mTc.551 The "mTc-sulfur colloid provides one such example and is usually described as 99mTc2S7, although its chemical composition remains uncertain. An improved method for the preparation of this... 

Zeeh J, Platt D. The aging liver structural and functional changes and their consequences for drug treatment in old age. Gerontology. 2002 48 121-127. 

There are abundant animal data detailing the effects of DEHP on liver structure and function. Rats and mice are most susceptible to the hepatic effects of DEHP, while dogs and monkeys are less likely to experience changes in the liver after exposure. In general, the data indicate that male rats are more susceptible to the hepatic effects of DEHP than are females. 

J.D. Yarbrough, J.E. Chambers, K.M. Robinson, Alterations in liver structure and functions resulting from chronic insecticide exposure, in Effects of Chronic Exposure to Pesticides on Animal System, J.E. Chambers, and J.D. Yarbrough, eds., Raven Press, New York, 1982. 

Haussinger, D. (1990). Nitrogen metabolism in liver Structural and functional organization and physiological relevance. Biochem. J. 267,281-290. 

Persistent cholestasis with concomitant inflammatory and connective tissue reactions leads to irreversible cholestasis and, after months/years, to biliary fibrosis with preserved liver structure or to (primary or secondary) biliary cirrhosis. (15, 18, 23, 55, 64, 70)... 

Fig. 28.12 Alcoholic cirrhosis with portal hypertension stenosis of the portal vein (see arrow) with stagnation of blood flow in the portal vein (VP) and portal flow reversal (blue = hepatofugal) as well as enhanced arterial flow (red). Arterial signals are visible in the flow profile. Inhomogeneous liver structure...

Chronic exposure to certain chemicals can cause cirrhosis, a marked alteration of the entire liver structure with both degenerative and proliferative changes observed, and neoplasia. 

From physiological and ultrastructural considerations, it would appear that the alkaline phosphatase of the bile canaliculi (the only liver structures that are histochemically positive) would have the same function as that assigned to the brush border of intestine and placenta. It may serve in membranes participating in the active transport of metabolites and ions into and out of the bile duct epithelium. The bile normally contains relatively low alkaline phosphatase activity, which can be considered enzyme produced by the bile canaliculi only. 

B-100 VLDL, LDL, IDL 100 540 Necessary for assembly and secretion of VLDL from the liver, structural protein of VLDL, IDL, LDL, ligand for LDL receptor Liver... 

Blumcke, S., Schwartzkopff, W., Lobeck, H., Edmondson, N. A., Prentice, D. E., andBlane, G. F. (1983). Influence of fenofibrate on cellular and subcellular liver structure in hyperlipidemic patients. Atherosclerosis 46, 105-116. 

Selective Biotransformation Potential. A number of factors might limit the possible extrapolation of results to the in vivo situation. Firstly, compounds may be degraded by different cells or mechanisms, e.g. due to acid conditions in the stomach, or by bacterial degradation in the lower parts of the G.I.-tract. Also, other organs may be involved in the biotransformation of a compound, possibly resulting in very specific metabolites. On the other hand, the isolation of hepatocytes results both in the disruption of the typical liver structure, and a selection of cell-types. This may be an important advantage of liver slices, especially now that their preparation has become much easier, faster and more reproducible (20, 21, 22, 23, 24). Last but not least, monolayer... 

Andersen, K.V. and Poulsen, F. M, 1993, The three-dimensional structure of acyl-coenzyme A binding protein from bovine liver structural refinement using heteronuclear multidimensional NMR spectroscopy. Journal of Biomolecular NMR 3, 271-284. 

The human liver specimens were obtained by biopsy at abdominal operations from patients with clinical diagnosis of cholecystitis and cholelithiasis. Hematoxylin-and-eosin slides were made of each specimen. Only those biopsy results which showed normal liver structure on histological examination were included in the series. Rat livers were obtained from male adult... 

FIGURE 6.6 Biotransformation and liver structure. Liver cells called hepatocytes are wedged between blood channels (sinusoids) and bile canals. Foreign chemicals that have been taken up into the bloodstream diffuse down their eoncentration gradients out of the bloodstream and into hepatocytes. There they are subject to biotransformation by Phase I and Phase II enzymes. The structurally transformed chemicals move out of the hepatocyte, entering either the blood sinusoid (smaller chemicals) or the bile canal (larger chemicals) or both (chemicals of intermediate size). Biotransformed chemicals that enter the bloodstream are eliminated by the kidneys. Biotransformed chemicals that enter the bile canals are eliminated in the feces. (Reprinted with permission from David Shier, Jackie Butler and Ricki Lewis, Hole s Human Anatomy and Physiology, 7th ed. [Dubuque Wm. C. Brown, 1996], 696.)... 

In human infectious hepatitis severe derangement of the liver structure occurs. Light microscopical studies as well as electron microscopy have revealed a wide spectrum of more or less pronounced alterations, including degeneration of the parenchymal cells and alterations of practically all cytoplasmic components of the hepatocytes (Schaffner and Popper, 1967). Hence, disturbances in the liver cell functions including alterations in the cholesterol and bile acid metabolism in this disease seem probable. How -cver, only few studies have been presented concerning bile acid metabolism. 

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