Pancreatic branch

The dorsal pancreatic artery is the first major pancreatic branch, usually coming off the splenic artery, although many variations have been described (right hepatic artery, SMA, and celiac artery) [15]. After supplying the dorsal surface of the neck of the pancreas, it divides into a left branch, the transverse pancreatic, and into a right branch (branches), which unites with the gastroduodenal or the superior pancreatoduodenal [14]. 

Spigos et al. [112] adopted a strict protocol that resulted in a remarkably low number of complications. The protocol included broad-spectrum antibiotics started 8-12 hours before the procedure and continued for 1-2 weeks, local antibiotics (such as gentamicin) suspended in the solution used to deliver the particulate embolic agents and administered through the angiographic catheter, strict attention to sterility (whole-body povidone-iodine bath or wide surgical scrub at the site of catheter insertion), selective catheterization with the catheter tip beyond pancreatic branches, effective pain control with narcotics or epidural anesthesia for 48 hours (which prevents the splinting that may... 

The hydrolysis of starch by salivary and pancreatic amylases catalyze random hydrolysis of a(l—>4) glycoside bonds, yielding dextrins, then a mixmre of glucose, maltose, and isomaltose (from the branch points in amylopectin). 

Products.—Considerable information concerning the mechanism of the enzymic hydrolysis of starch has been obtained from investigations of the action of purified maltase-free pancreatic amylase on a number of different substrates. The substrates studied were ordinary unfractionated but exhaustively defatted10 potato and com starches a branched chain substrate, waxy maize starch and amylose, the linear component of corn starch.41 69 eo f4 These investigations included comparisons not only of the rates of the hydrolysis of the different substrates but also of the products formed from them. 

With the same concentration of pancreatic amylase reacting under comparable conditions, no marked differences were observed in the rate of the hydrolysis of any of the unfractionated ordinary starches studied.41,69 6064 On the other hand significant differences were observed in the rate of the hydrolysis of straight and of branched chain substrates. The data60 in Table IV show that waxy maize starch is hydrolyzed more slowly than unfractionated corn starch and much more slowly than the... 

The carboxypeptidases are released from their inactive precursors in the pancreatic juice of animals. The most studied example is bovine carboxypeptidase A, which contains one mole of zinc per protein molecular weight of 34 500. These enzymes cleave the C-terminal amino acid residue from peptides and proteins, when the side-chain of the C-terminal residue is aromatic or branched aliphatic of l configuration. At least the first five residues in the substrate affect the activity of the enzyme. The enzyme also shows esterase activity. Esters and peptides inhibit each other competitively, indicating that the peptidase and esterase sites overlap, even if they are not the same. 

In these a-amylase reactions, glucose is not the primary product. Glucose is formed as a secondary product in the hydrolysis of maltotriose, maltotetraose and branched dextrins. Using 14C-reducing end labeled maltodextrins, G3 to G8, Robyt and French19 showed that porcine pancreatic a-amylase has different specificities for hydrolyzing the different linkages of the maltodextrins. The different frequencies for... 

The doubly branched dextrins, 64,66-di-a-D-glucopyranosylmaltohexaose and 63,65-di -a-D-glucopyranosylmaltopentaose, isolated by Kainuma and French17 after action of porcine pancreatic a-amylase on waxy maize starch, established that the a-(l—>-6) branch linkages could be as close as having one glucosyl unit between them. No saccharides were found that indicated that the branch linkages could be adjacent to each other. 

Fig. 8.11 Arterioportography coeliacography with good visualization of the branches of the coeliac trunk including the fine ramifications. Small hypervascularized haemangioma ( ) S = spleen. (The pancreatic vessels are also visible.) Normal depiction of the portal vessels in the venous phase...

Anomalies are described as a missing portal vein and intrahepa-tic branches with simultaneous hyperplasia of the hepatic artery. The portal vein and its branches may also be located in front of the duodenum and the pancreatic head. Sometimes, even a... 

Sundaram, S. Dayan, A.D. Effects of a cholecystokinin receptor antagonist on rat exocrine pancreatic response to raw soya flour. Human Exp. Toxicol. 1991,10, 179-182. Expert Working Group (Safety) of ICH. FDA Guidance for Industry ich-slc dose selection for carcinogenicity studies of pharmaceuticals. Drug Information Branch, HFD-210, CDER, 5600 Fishers Lane, Rockville, MD 20857 accessed Sept. 22, 1998, http //www.fda.gov/CDER/ guidance/index, htm. 

Saliva and pancreatic juice both contain a-amylase. The activity of this enzyme in saliva is not significant compared with that in the pancreatic juice released into the gut. Release of amylase from the pancreas is controlled by a mechanism similar or identical to the one that stimulates the release of tr)rpsinogen, namely by the influence of CCK on the exocrine pancreas. Amylase catalyzes the hydrolysis of starch at interior positions rather than at the ends of the polymer. This activity yields products such as maltose and longer-chain-length oligomers of glucose. Also, amylase does not catalyze the hydrolysis of starches at branching points. Therefore, small branched-chain structures called dextrins are formed that are not hydrolyzed by the er zyme. 

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