HA, Hepatic Artery

Figure 21.3 Histochemical analysis of / -galactosidase gene expression in liver. Ten pa of pCMV-LacZ plasmid DNA were injected into a mouse via the tail vein using the hydrodynamics-based procedure, / -galactosidase gene expression was assayed eight hours post injection. HV, hepatic vein HA, hepatic artery PV, portal vein (50x). (see Color Plate 15)...

D, Bile duct HA, hepatic artery PV, porta vein CK centra vein. (From Zakim O, Boyer TD. Hepawhgf.A textbook of liver disease, 3rd ed. Philadelphia WB Saunders, 1996 10.)... 

PV postal vein SD space of Disse HA hepatic artery SC stellate cells PF portal fibroblasts CV central vein S sinusoids H hepatocytes... 

Type 6 common HA arising directly from the aorta HA, hepatic artery SMA, superior mesenteric artery. 

BI-RADS breast imaging reporting and data system HA hepatic artery... 

Fig.1.3. In colour Doppler, flow towards the transducer is coded in reddish tints so that both the portal vein and the hepatic artery have similar colours. Hepatic vein branches are seen in blue. HA, hepatic artery HV, hepatic vein PV, portal vein...

The most common adverse events reported with sirolimus are leukopenia (20%), thrombocytopenia (13% to 30%), and hyperlipidemia (38% to 57%).11,31 Other adverse effects include delayed wound healing, anemia, diarrhea, arthralgias, rash, and mouth ulcers. Sirolimus has an FDA black-box warning in newly transplanted liver and lung recipients.11 In liver transplant recipients, use of sirolimus immediately after transplant is associated with an increased risk of hepatic artery thrombosis, graft loss, and death. In lung transplant... 

Classically the liver has been divided into hexagonal lobules centred around the terminal hepatic venules. Blood enters the liver through the portal tracts that are situated at the corners of the hexagon. The portal tracts are triads of a portal vein, an hepatic artery, and a common hepatic bile duct. The vast expanse of hepatic tissue, mostly consisting of parenchymal cells (PC) or hepatocytes, is serviced via terminal branches of the portal vein and hepatic artery, which enters the tissue at intervals. The hepatocytes are organized into cords of cells radially disposed about the central hepatic venule. Between these cords are vascular sinusoids that transport the blood to the central hepatic venules. The blood is collected through the hepatic venules into the hepatic vein which exits the liver into the inferior vena cava (Figure 4.1). 

Figure 4.1. Schematic representation of the architecture of the liver. Blood enters the liver through the portal vein (PV) and hepatic arteries (HA), flows through the sinusoids, and leaves the liver again via the central vein (CV). KC, Kupffer cells SEC, sinusoidal endothelial cells HSC, hepatic stellate cells BD, bile duct. Modified from reference 98.

Floxuridine (FUDR) is the nucleoside of 5-fluo-rouracil that is readily converted into 5-fluorouracil in vivo. It has similar pharmacological effects but is preferred to 5-fluorouracil for hepatic arterial infusions because it is more extensively metabolized in the liver than 5-fluorouracil, with less systemic toxicity. 

Fluorouracil is normally given intravenously (Table 55-3) and has a short metabolic half-life on the order of 15 minutes. It is not administered by the oral route because its bioavailability is erratic due to the high levels of the breakdown enzyme dihydropyrimidine dehydrogenase present in the gut mucosa. Floxuridine (5-fluoro-2 -deoxyuridine, FUDR) has an action similar to that of fluorouracil, and it is only used for hepatic artery infusions. A cream incorporating fluorouracil is used topically for treating basal cell cancers of the skin. 

Whether rAAV distributes to sperm cells has been of significant concern because of the possibility of introducing mutations in sperm. While AAV DNA can be found in the testes of rodents, rabbits, and dogs following either hepatic arterial or IM injections, these signals appear to be localized to the testis basement membrane and the interstitial space, with no intracellular signal observed. In mice and rats, there was a dose-dependent increase of vector expression in gona-... 

MODIFICATIONS OF THE METHOD This method has been widely used for studying carbohydrate and lipid intermediary metabolism (Herling et al. 1998) as well as drug metabolism (Milne et al. 1997 and Milne et al. 2000, Vuppugalla 2004). Many variations have been reported predominantly with respect to the animal species used. Chaib et al. (2004) compared isolated perfused livers of rats with those of guinea pigs. Den Butter (1994) used livers from rabbits. Further modifications are related to the direction of perfusion via hepatic artery or portal vein or both simultaneously or in connection with the isolated jointly perfused small intestine (Stumpel et al. 1997 and Stumpel et al. 2000) as well as the continuous perfusion in a recirculated (see above) or open (non-recirculated) manner (Lopez et al. 1998). 

Figure 28.1. Comparison of structural liver lobule with functional acinar regions. The liver lobule is centered on the terminal hepatic venule (THV), also called the central vein, and assumes a roughly hexagonal shape with its vertices at the portal triads, which contain the portal vein (PV), hepatic artery (HA), and bile duct (BD). The liver acinus is centered upon the tract of blood vessels that branch from the hepatic artery and portal vein of the portal triads. Hepatocytes within the acinus are grouped within functional zones 1,2, and 3 located at increasing distances from the vascular tracts that interconnect adjacent portal triads.

Outside the liver the common hepatic duct is joined by the cystic duct of the gallbladder and becomes the common bile duct (CBD). The extrahepatic and intrahepatic ducts are supplied with blood by a fine network of tiny arterial branches that originate from the hepatic and gastroduodenal arteries. As it has no other blood supply, the biliary tree is particularly susceptible to ischaemic injury, such as hepatic artery thrombosis or injury to the biliary plexus during laparoscopic surgery. This can result in extrahepatic and complex hilar and perihilar ischaemic strictures of the biliary tree. 

As mentioned above, the liver has a dual blood supply. The hepatic artery delivers material from the systemic circulation and the portal blood flow delivers directly from the gastrointestinal system. The portal system is involved in the first pass effect , where the nutrients and xenobiotics that are absorbed from the stomach and intestines are filtered through the liver before reaching the systemic circulation (Treinen-Moslen, 2001). The space of Disse allows close contact between circulating plasma, plasma proteins, and hepatocytes, allowing for rapid diffusion of lipophilic compounds across the hepatocyte membrane. Some compounds are specifically taken up by sinusoidal transporters, including... 

Treatment If it is possible, elective resection is indicated. (98) However, due to cardiac or (increasing) hepatic insufficiency, invasive techniques cannot usually be attempted. External irradiation may be used in an effort to minimize the tumour. Ligature or embolization of the afferent hepatic artery is sometimes indicated. Steroid therapy has proved unsuccessful. The use of interferon-a is a new therapeutic approach tumour regression is accelerated and cardiac insufficiency is compensated. (103) Liver transplantations have also been carried out successfully. This infantile, benign tumour may regress with increasing age. 

Once detected, an aneurysm of the hepatic artery requires immediate treatment. Up to a certain size, intrahepatic aneurysms are treated by angiographic embolization. Coagulation by means of direct thrombin injection has also been described. (130) Larger aneurysms are treated by vascular surgery (ligation, vascular reconstruction, resection). (132, 137)... 

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