Pancreatic tissue

Insulin is one of the important pharmaceutical products produced commercially by genetically engineered bactera. Before this development, commercial insulin was isolated from animal pancreatic tissue. Microbial insulin has been available since 1982. The human insulin gene is introduced into a bacterium like E. coli. Two of the major advantages of insulin production by microorganisms are that the resultant insulin is chemically identical to human insulin, and it can be produced in unlimited quantities. 

Sparmann G, Behrend S, Merkord J, Kieine HD, Grasser E, Ritter T, Liebe S, Emmrich J (2001) Cytokine mRNA ieveis and iymphocyte infiitration in pancreatic tissue during experimentai chronic pancreatitis induced by dibutyitin dichioride. Digestive Diseases and Sciences, 46 1647-1656. 

Dabrowski, A., Gabryelewicz, A. and Chwiecko, M. (1991). Products of lipid peroxidation and changes in sulphydryl compounds in pancreatic tissue of rats with caerulein-induced acute pancreatitis. Biochem. Med. Metab. Biol. 46, 10-16. 

Hereditary hemochromatosis is an autosomal recessive disease of increased intestinal iron absorption and deposition in hepatic, cardiac, and pancreatic tissue. Hepatic iron overload results in the development of fibrosis, hepatic scarring, cirrhosis, and hepatocellular carcinoma. Hemochromatosis can also be caused by repeated blood transfusions, but this mechanism rarely leads to cirrhosis. 

Acute pancreatitis can progress to several distinct consequences. Pancreatic fluid collections and pancreatic abscesses can form during the course of acute pancreatitis. Pancreatic necrosis can occur when pancreatic enzymes damage the pancreatic tissue or when pancreatic abscesses become secondarily infected. This infection is usually due to bacteria that are normally found in the gastrointestinal tract, including Escherichia coli, Enterobacteriaceae, Staphylococcus aureus, viridans group streptococci, and anaerobes. 

Traditionally, commercial insulin preparations were produced by direct extraction from pancreatic tissue of slaughterhouse pigs and cattle, followed by multistep chromatographic purification. However, the use of animal-derived product had a number of potential disadvantages, including ... 

Traditionally, glucagon preparations utilized therapeutically are chromatographically purified from bovine or porcine pancreatic tissue. (The structure of bovine, porcine and human glucagon is identical, thus eliminating the possibility of direct immunological complications). Such commercial preparations are generally formulated with lactose and sodium chloride and sold in freeze-dried form. Glucagon, 0.5-1.0 units (approximately 0.5-1.0 mg freeze-dried hormone), is administered to the patient by s.c. or i.m. injection. 

Chymotrypsin has also been utilized to promote debridement, as well as the reduction of soft tissue inflammation. It is also used in some opthalmic procedures, particularly in facilitating cataract extraction. It is prepared by activation of its zymogen, chymotrypsinogen, which is extracted from bovine pancreatic tissue. 

In most individuals, CP is progressive and loss of pancreatic function is irreversible. Permanent destruction of pancreatic tissue usually leads to exocrine and endocrine insufficiency. 

Surgical biopsy of pancreatic tissue through laparoscopy or laparotomy is the gold standard for confirming the diagnosis of CP. 

To prevent self-digestion, the pancreas releases most proteolytic enzymes into the duodenum in an inactive form as proenzymes (zymogens). Additional protection from the effects of premature activation of pancreatic proteinases is provided by proteinase inhibitors in the pancreatic tissue, which inactivate active enzymes by complex formation (right). 

Insulin Diabetes mellitus Porcine/bovine pancreatic tissue... 

The quantity of purified insulin obtained from the pancreas of one pig satisfies the requirements of one diabetic for 3 days. The supply of pancreatic tissue is dependent upon the demand for meat, which does not necessarily correlate with the increasing worldwide incidence of diabetes. Recombinant DNA technology provides an obvious way to ensure future adequate supply of insulin. 

The islet cells transplanted into humans are obtained from pancreatic tissue of deceased human donors (Figure 8.9). Implantation of these cells in recipients displaying a competent immune system would, at best, be of transient therapeutic benefit. The ensuing immune response would quickly destroy the foreign cells. Studies conducted thus far in humans have utilized diabetic patients who have received kidney transplants, as these are already subject to immunosuppressive therapy. However, a major stumbling block to the widespread adoption of this therapeutic approach is, predictably, the requirement to induce concurrent immune suppression. 

Shen J, Person MD, Zhu J et al. Protein expression profiles in pancreatic adenocarcinoma compared with normal pancreatic tissue and tissue affected by pancreatitis as detected by two-dimensional gel electrophoresis and mass spectrometry. Cawcer Rex 2004 64 9018-9026. 

The major action of sulfonylureas is to increase insulin release from the pancreas (Table 41-5). Two additional mechanisms of action have been proposed—a reduction of serum glucagon levels and closure of potassium channels in extra pancreatic tissue (which are of unknown but probably minimal significance). 

Acute pancreatitis is a disease caused by obstruction of the normal pathway by which pancreatic secretions enter the intestine. The zymogens of the proteolytic enzymes are converted to their catalyt-ically active forms prematurely, inside the pancreatic cells, and attack the pancreatic tissue itself. This causes excruciating pain and damage to the organ that can prove fatal. ... 

Preparation of Insulins. Until the early 1980s insulin for therapeutic purposes was produced almost exclusively by extraction from beef and pork pancreases. Between 100 and 400 mg of insulin can be obtained from each kg of pancreatic tissue, and it has been estimated that there would be sufficient supplies of animal insulin to meet the requirements of diabetic patients into the twenty-first century (2). Through modem purification procedures animal insulins can be prepared in essentially pure form, which eliminates the possibility of developing antibodies against impurities in the insulin preparations. However, patients treated with purified insulins still develop antibodies to insulin, suggesting that differences in the primary structures of these insulins might stimulate antibody production. Therefore, enzymatic and biosynthetic methods have been developed for the preparation of therapeutic insulin identical to human insulin. 

This protein is extracted from pancreatic tissues. This protein occurs in a-form and /1-form, but the a-form is used as chiral selector in liquid chromatography. The molecular mass is 25,000, with an isoelectric point of 8.1-8.6. It is inhibited by metal ions. The protein is useful for chiral resolution of amino acids and amino esters. 

On the basis of fluorescence studies Nardi and Seipel 491) assumed that i.v. injections of berberine, palmatine, and columbamine result in selective localization of these substances in the pancreatic tissue. According to Schatz et al. 492), who analyzed different rat tissues, berberine was not selectively localized in the pancreas though it produced yellow fluorescence in that organ. This problem has been studied in detail 493, 494). The quantitative results showed that shortly after administration, berberine was deposited mainly in the... 

Trypsinogen-Activating Peptide (TAP). The most reliable way to assess trypsinogen activation is to measure trypsinogen-activation peptide (TAP) in serum, urine, pancreatic tissue, or ascitic fluid (H5, M4). Studies on TAP in... 

Poly-C-SpecificRibonuclease (P-RNase) (EC3.1.27.5). Warshawand Fournier (W3) showed that an increase in plasma enzyme activity of pancreatic P-RNase in patients with AP may indicate necrotic lesions, and is one of the few direct markers of pancreatic tissue injury (Nl, W4). Due to the time-consuming and cumbersome nature of the P-RNase assay procedure and the development of effective visualization techniques providing direct information on the structure of the inflamed pancreas, the diagnostic utility of the P-RNase assay has not been extensively studied (Table 3). 

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