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PubMed1994

Evaluation of a specific immunoinhibition method for the determination of pancreatic alpha-amylase.

Ten clinical centres in Italy participated in an evaluation of a pancreas-specific alpha-amylase assay using two monoclonal antibodies. Comparisons with electrophoretic methods showed good agreement in the reference range, but systematic deviations above it. The diagnostic information of the two methods appeared substantially different if the percentage values from electrophoresis were compared with activity units from the immunoinhibition method, but became similar if the two methods were compared on the basis of activity units. Reference intervals determined for serum/plasma corresponded to those previously published, but those determined for urine differed slightly from the published values. Clinical sensitivities for the assessment of acute pancreatitis (n = 134) were found as follows. Related to the upper limit of the control group (n = 141), the pancreatic alpha-amylase, total alpha-amylase and lipase showed sensitivities of 0.94, 0.87 and 0.93, respectively. When the cut-off point was set at the three-fold upper limit of the control group, sensitivities of 0.73, 0.53 and 0.70 were found, and the specificity was 1.00 for all three methods. Based on this commonly used higher cut-off point, the determination of lipase in addition to pancreatic alpha-amylase enhanced the sensitivity in the recognition of acute pancreatitis by 8%; conversely, the determination of pancreatic alpha-amylase in addition to lipase increased the number of true positive results by 13%. The high practicability and interlaboratory transferability documented in the results of the collaborative study show that the pancreatic alpha-amylase assay is very useful for recognizing pancreatic inflammations, especially in combination with lipase.

Acute Disease↗
PubMedDate not supplied

[Alpha-amylase as an occupational allergen in baking industry employees].

In a group of 226 bakers and pastry makers and in 88 students of a training school for bakers, we evaluated skin sensitization to the common allergens, wheat and alpha amylase. Skin prick tests were positive to the enzyme in 17 exposed subjects (7.5%) and in one student with previous occupational exposure as a baker; 27 exposed subjects (11.9%) and 2 students were sensitized to wheat. Among the 42 exposed workers who complained of work-related symptoms, 12 (28.6%) cases were skin positive to amylase and 17 (42.9%) to wheat. Among the 17 workers who were positive to amylase, 16 were also sensitized to wheat and/or common allergens, 12 complained of symptoms at work but since in many cases there was a positive response to wheat, too, it is impossible to speculate on the role of each allergen in inducing symptoms. One case, with work-related rhinoconjunctivitis, had skin sensitization only to alpha amylase but no specific IgE in the serum. These findings confirm that bakers are at risk of sensitization not only to wheat allergen but also to amylase from Aspergillus oryzae. The enzyme should be included in the list of substances to be tested among bakers in whom an occupational allergy is suspected, but particular care should be taken in evaluating the cutaneous response, especially if compared to wheat wheals. Further investigations are also needed to identify the source of risk and to better define the characteristics of the enzyme and the relationship between skin reaction to amylase, sensitization to wheat and atopy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1978

Effect of glucagon infusion on the renal clearance of amylase relative to creatinine.

Recent data seem to support a tubular defect as the mechanism of the elevated renal clearance of amylase relative to creatinine in acute pancreatitis. Glucagon has been proposed by some to be an important factor in this phenomenon. To examine the role of glucagon as this "tubular dysfunction factor", we investigated the effect of intravenously infused glucagon on the fractional excretion of amylase and the tubular handling of a low molecular weight protein, beta2 microglobulin, in normal, healthy volunteers. At glucagon levels far in excess of those seen in pancreatitis, the clearance ratio of beta2 microglobulin relative to creatinine increased, whereas the clearance ratio of amylase relative to creatinine did not increase above the normal range. The dissociation between beta2 microglobulin clearance and amylase clearance allows one to question the theory that tubular dysfunction is the mechanism of the elevated renal clearance of amylase relative to creatinine in acute pancreatitis. Glucagon does not appear to be the sole factor responsible for the elevation of renal clearance of amylase relative to creatinine in acute pancreatitis.

Adult↗
PubMed1977

Differential serum amylase determination by use of an inhibitor, and design of a routine procedure.

We describe a new method for measuring pancreatic and salivary-type amylases in serum that requires no electrophoresis or chromatography. An inhibitor protein (from wheat) with a 100-fold greater specificity for human salivary than for human pancreatic amylase was used to analyze mixtures of the two enzymes. The concentration of pancreatic and salivary amyalase was determined in 141 normal sera (72 men and 69 women). Statistically significant differences were found for serum pancreatic amylase between mean and women, higher values being shown in women. No sex-related difference was found for the salivary component of serum amylase. With this method, the increase in serum amylase activity in pancreatitis was shown to be attributable to the pancreatic component. In mumps, the increase is attributable to the salivary component. In pancreatic insufficiency, serum pancreatic amylase activities were significantly lower than in the controls. Our method is simple and rapid; our results agree well with those of other authors who used chromatographic or electrophoretic methods.

Adolescent↗
PubMed1996

[A case of ectopic amylase-producing lung cancer].

A case of amylase-producing lung cancer is reported. A 58-year-old man was admitted to our hospital because of abnormal shadow on chest X-rays. Transbronchial lung biopsy showed adenocarcinoma at the right upper lobe. Amylase levels were elevated to 915 IU/l in the serum and 960 IU/l in urine. Amylase isozyme pattern identified "salivary-type" amylase. Right upper lobectomy was performed. Both serum and urine, amylase levels were decreased within normal limits after operation. Enzyme labeled immunoperoxidase method on this specimen proved that tumor cells were producing amylase ectopically.

Adenocarcinoma↗
PubMed1997

[Diffuse bronchiolo-alveolar cell carcinoma that produced both amylase and CA19-9].

A 68-year-old man who worked as an editor was admitted to Aichi Medical University Hospital due to dyspnea on exertion and emaciation. The patient had noticed rapid weight loss during diet therapy for diabetes mellitus that started in the beginning of July, 1993. Laboratory examinations revealed elevated levels of LDH and amylase in serum. Ultrasonography disclosed minimal ascites. Dyspnea on exertion developed in September, 1993. Chest roentgenography showed diffuse bilateral small nodular or reticular opacities. CT-guided percutaneous needle aspiration was done and cytologic examination of a specimen of lung tissue revealed papillary adenocarcinoma. The diagnosis was bronchiolo-alveolar carcinoma. Serum levels of amylase were elevated. The amylase isozyme pattern was of the salivary type. Serum levels of CA19-9 and CEA were also elevated. The patient died of respiratory failure on December 4, 1993. Postmortem examination revealed diffuse small nodules in both lungs. Examination of the nodules showed bronchiolo-alveolar cell carcinoma. The tumor cells stained positively for amylase (salivary type, not pancreatic type) CA19-9, and CEA by the avidin biotin complex method, but they were immunohistologically negative for AFP. We conclude that this lung cancer produced amylase, CA19-9, and CEA. We know of only a few reports of cases in which lung cancer produced both amylase and CA19-9.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1997

Amylase concentration of drainage fluid after total gastrectomy.

BACKGROUND: Pancreatic fistula is a serious complication of total gastrectomy with splenectomy. The amylase content of drainage fluid was examined and its usefulness for predicting pancreatic complications after gastrectomy was evaluated. METHODS: The amylase concentration of the fluid in the peripancreatic drain was determined prospectively in 102 patients who underwent total gastrectomy in 1995. RESULTS: Pancreatic fistula developed in 13 patients, whose drainage fluid amylase levels on the first postoperative morning were significantly higher than those of patients without fistula formation. Among 27 patients with amylase levels exceeding 4000 units, eight later developed pancreatic fistula, while only five (7 per cent) of 68 with amylase levels below 4000 units did so. All complications were successfully managed and there were no deaths. CONCLUSION: Determination of drainage fluid amylase levels is a simple and useful method for the prediction of pancreatic fistula formation and may help to plan appropriate management.

Adult↗
PubMed1998

Production and properties of a raw-starch-degrading amylase from the thermophilic and alkaliphilic Bacillus sp. TS-23.

The optimum temperature and initial medium pH for amylase production by Bacillus sp. TS-23 were 55 degrees C and 8.5 respectively. Maximum amylase activity was obtained in a medium containing peptone and soluble starch as nitrogen and carbon sources. Activity staining revealed that two amylases with molecular masses of 150 and 42 kDa were produced when maltose, soluble starch or amylose was used as carbon source for growth, whereas only the 150 kDa protein was detected in the medium containing water-insoluble carbon sources. A raw-starch-degrading amylase was purified from culture supernatant of Bacillus sp. TS-23. The molecular mass of the purified amylase was estimated at 42 kDa by electrophoresis. The enzyme had a pI of 4. 2. The optimal pH and temperature for activity were 9.0 and 70 degrees C respectively. The thermoactivity of the purified enzyme was enhanced in the presence of 5 mM Ca2+; under this condition, enzyme activity could be measured at a temperature of 90 degrees C. The enzyme was strongly inhibited by Hg2+, Pb2+, Zn2+, Cu2+ and EDTA, but less affected by Ni2+ and Cd2+. The enzyme preferentially hydrolysed high-molecular-mass substrates with an alpha-1, 4-glucosidic bond except glycogen. The raw starches were partly degraded by the purified amylase to yield predominantly oligosaccharides with degrees of polymerization 3, 4 and 5.

Bacillus↗
PubMedDate not supplied

Amylase activity of parotid saliva in acute and chronic pancreatitis.

The activity of the alpha-amylase was estimated in the parotid resting saliva of 17 subjects without evidence of pancreatic disease, 17 patients with chronic relapsing pancreatitis in the intervals between acute attacks, and also in 4 patients with acute pancreatitis and 3 patients with an acute attack of chronic relapsing pancreatitis. In the patients with chronic relapsing pancreatitis between attacks the concentration, output and specific activity of the salivary amylase were significantly lowered. The patients with acute pancreatitis exhibited salivary amylase concentrations in the uppper normal to grossly supranormal range, whereas those of the patients with acute attacks of chronic relapsing pancreatitis were distinctly reduced. Unlike the amylase output, the amylase concentration was independent of the rate of salivary flow. Simultaneous infusion of secretin and pancreozymin produced a significant increase in the parotid salivary amylase levels in both the patients without pancreatic disease and in those with chronic relapsing pancreatitis between acute attacks.

Acute Disease↗
PubMed1964

PREFERENTIAL SYNTHESIS OF ALPHA-AMYLASE BY BACILLUS STEAROTHERMOPHILUS IN THE PRESENCE OF 5-METHYL-TRYPTOPHAN.

Welker, N. E. (Western Reserve University, Cleveland, Ohio), and L. Leon Campbell. Preferential synthesis of alpha-amylase by Bacillus stearothermophilus in the presence of 5-methyl-tryptophan. J. Bacteriol. 87:828-831. 1964.-Washed-cell suspensions of Bacillus stearothermophilus induced with pure maltose preferentially synthesized alpha-amylase in the presence of 5-methyl-tryptophan (5-MT). 5-MT did not inhibit the formation of active alpha-amylase or the incorporation of proline-C(14) into alpha-amylase. In contrast, p-fluorophenylalanine inhibited the formation of active alpha-amylase by 92% and the incorporation of proline-C(14) into the enzyme by 95%. p-Fluorophenylalanine and 5-MT inhibited cellular protein synthesis, as measured by proline-C(14) incorporation, by 74 and 72%, respectively.

Amylases↗
PubMed1983

Continuous production of maltooligosaccharides from glucose 1-phosphate by amylase-phosphorylase reactor.

Using an ultrafiltration cell, the continuous production of maltose and a mixture of other oligosaccharides was achieved by the combined action of alpha- or beta-amylase and phosphorylase. For the beta-amylase-phosphorylase system, a steady production of maltose was obtained until the beta-amylase was inactivated. For the alpha-amylase-phosphorylase system, it was difficult to maintain a stable production of oligosaccharides, probably due to the destruction of substrate glycogen by random cleavage by alpha-amylase.

Amylases↗
PubMed2001

Ontogeny of alpha-amylase gene expression in sea bass larvae (Lates calcarifer).

The enzymatic activities of alpha-amylase and its corresponding messenger RNA levels in developing sea bass (Lates calcarifer) larvae were studied from hatching until 27 days post hatching (dph). An increasing activity of amylase enzyme was measured until 5 dph, and the activity gradually decreased thereafter and reached a constant level by 12 dph. To achieve a better understanding of the molecular mechanisms underlying amylase expression, we have cloned and sequenced a 318-bp fragment of alpha-amylase complementary DNA. Based on this sequence, a real-time reverse transcriptase polymerase chain reaction technique to monitor the changes in the mRNA levels in the larvae was developed. A correlation between enzymatic activity and mRNA level of alpha-amylase could be demonstrated during the early development of sea bass larvae. This suggests that the changes in alpha-amylase are controlled at least at the transcriptional level during early larval development of sea bass.

Journal Article↗
PubMed1979

Enzymic Mechanism of Starch Breakdown in Germinating Rice Seeds: 8. Immunohistochemical Localization of beta-Amylase.

Rabbit antiserum against beta-amylase isolated from germinating seeds of rice was produced, and its specific cross-reactivity with beta-amylase was confirmed by means of Ouchterlony double immunodiffusion and immunoelectrophoresis procedures. The cellular localization of beta-amylase was studied by indirect fluorescence microscopy of thin sectioned germinating rice seed specimens (1-day stage) which had been fixed and treated with purified rabbit anti-beta-amylase immunoglobulin G followed by conjugation with fluorescein isothiocyanate-labeled goat antirabbit immunoglobulin G. It has been demonstrated that beta-amylase is uniformly associated with the periphery of starch granules in the starchy endosperm cells. The finding is discussed in relation to the general notion concerning the presence of the latent form of beta-amylase bound to protein bodies in cereal seeds.

Journal Article↗
PubMed1981

Enzymic Mechanism of Starch Breakdown in Germinating Rice Seeds: 10. IN VIVO AND IN VITRO SYNTHESIS OF alpha-AMYLASE IN RICE SEED SCUTELLUM.

Scutellar tissues were dissected from germinating rice seeds and the incorporation of [(35)S]methionine into the alpha-amylase molecule was examined by in vivo and in vitro assay systems. Immunoprecipitation with monospecific anti-alpha-amylase immunoglobulin G raised against the purified enzyme preparation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography were used to identify alpha-amylase and its possible precursor molecule. Using freshly prepared scutellar tissues, it was demonstrated that alpha-amylase is synthesized de novo in the scutellar epithelium and secreted into endosperm. The synthesis of alpha-amylase directed by the polyadenylic acid-containing ribonucleic acid isolated from the scutellar tissues was also established using the translation system of either wheat germ extract or reticulocyte lysate. The immunoprecipitable product obtained in the in vitro translation system was smaller in molecular weight than that synthesized in vivo on the basis of mobilities in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Results are discussed in relation to the processing of the nascent polypeptide precursor of the enzyme molecule and the introduction of the oligosaccharide chain to the cleaved polypeptide to make up the mature form of alpha-amylase.

Journal Article↗
PubMed1982

Effect of Ethylene on the Release of alpha-Amylase through Cell Walls of Barley Aleurone Layers.

A large portion of the gibberellic acid (GA(3))-induced alpha-amylase in isolated aleurone layers is transported into the incubation medium. In the presence of GA(3) and ethylene, an even larger portion of the enzyme is found in the medium. Employing an acid washing technique developed by Varner and Mense (Plant Physiol 1972 49:187-189), it was observed that ethylene significantly reduces the amount of alpha-amylase trapped by the thick cell walls of aleurone layers. However, the amount of enzyme remaining in the cell (within the boundary of plasma membrane) is not affected by ethylene. Ethylene has no observable effect on membrane formation as measured by the incorporation of [(32)P]orthophosphate into phospholipids. Because of these observations it is suggested that ethylene enhances the release of alpha-amylase, i.e. transport of alpha-amylase across cell walls, but not the secretion of alpha-amylase, i.e. transport of alpha-amylase past the barrier of plasma membrane. The possible mechanism of this ethylene effect is discussed.

Journal Article↗
PubMed1982

Ethylene effects on amylase activity from isolated barley aleurone layers : possible modification by proteolytic enzymes.

The effect of protease inhibitors on the response of gibberellic acid-treated barley aleurone layers to ethylene was examined. In the absence of protease inhibitors, ethylene plus gibberellic acid initially increased the production of amylase activity relative to layers incubated with gibberellic acid alone. Exposure to ethylene plus gibberellic acid for 48 hours or longer, however, led to depressed levels of amylase activity compared to samples incubated with gibberellic acid in hydrocarbon-free air.The direct assay of proteolytic activity revealed a small increase in activity in response to ethylene. The significance of this response was probed further by including inhibitors of barley proteases in the incubation medium. When potassium bromate was introduced, ethylene did not cause any alteration in amylase activity compared to samples incubated in hydrocarbon-free air. However, in the presence of N-ethylmaleimide, ethylene treatment induced a 52% increase in amylase activity recovered from samples after 48 hours. These results suggest that proteases contribute to the loss of amylase activity in response to ethylene and thus alter the apparent effect of ethylene on amylase synthesis. The effect of protease inhibitors on other hydrolases is also discussed.During the incubation period, the pH of the medium declined significantly. However, ethylene had no effect on the extent of this decline.

Journal Article↗
PubMed1982

Characterization of the alpha-Amylases Synthesized by Aleurone Layers of Himalaya Barley in Response to Gibberellic Acid.

The gibberellic acid (GA(3))-induced alpha-amylases from the aleurone layers of Himalaya barley (Hordeum vulgare L. cv Himalaya) have been purified by cycloheptaamylose-Sepharose affinity chromatography and fractionated by DEAE-cellulose chromatography. Four fractions (alpha-amylases 1-4) were obtained which fell into two groups (A and B) on the basis of a number of characteristics. Major differences in serological characteristics and in proteolytic fingerprints were found between group A (alpha-amylases 1 and 2) and group B (alpha-amylases 3 and 4). Also, the lag time for appearance of group B enzyme activity was longer than for group A, and the appearance of group B required higher GA(3) levels than group A. The components of each group behaved similarly, although differences in proteolytic fingerprints were detected.These results together with those from other studies indicate that GA(3) differentially controls the expression of two alpha-amylase genes or groups of genes giving rise to two groups of alpha-amylases with many different properties.

Journal Article↗
PubMed1983

Effects of abscisic Acid and ethylene on the gibberellic Acid-induced synthesis of alpha-amylase by isolated wheat aleurone layers.

Gibberellic acid-induced alpha-amylase synthesis in wheat aleurone layers (Triticum aestivum L. var Potam S-70) escaped from transcriptional control 30 h after addition of the hormone, as evidenced by the tissue's loss of susceptibility to cordycepin. Abscisic acid inhibited the accumulation of alpha-amylase activity when added to the tissue during this cordycepin-insensitive phase of enzyme induction. alpha-Amylase synthesis was not restored by the addition of cordycepin, indicating that the response to abscisic acid was not dependent upon the continuous synthesis of a short lived RNA. When ethylene was added simultaneously or some time after abscisic acid, the accumulation of alpha-amylase activity was sustained or quickly restored. The loss of susceptibility to cordycepin was completely prevented when aleurone layers were incubated with a combination of gibberellic and abscisic acids from the start of the induction period. This effect of abscisic acid was not reversed by ethylene. On the basis of these observations, it is suggested that abscisic acid inhibits both the transcription and translation of alpha-amylase mRNA, and that only the latter site of action is susceptible to reversal by ethylene.The rate of incorporation of [methyl-(14)C]choline into phospholipids was also inhibited by abscisic acid. Ethylene reversed this effect. The effects of abscisic acid and ethylene on phospholipid synthesis were not dependent upon the presence of gibberellic acid. No direct relationship was found between the control of alpha-amylase synthesis and membrane formation by abscisic acid and ethylene.

Journal Article↗