Isolated Amylase Deficiency in Children and Its Clinical Implication.

OBJECTIVES: Among the 3 lines of pancreatic enzymes, amylase secretion develops last and it is not detected in duodenal aspirates of infants in the first month after birth. The aim of this study was to assess the prevalence and symptoms of isolated amylase deficiency in children. METHODS: During a 6-year period, we performed endoscopic pancreatic function tests (ePFT) in 712 children. Isolated amylase deficiency was defined as activity that was below the third percentile of our referenced population with normal lipase and protease activities. RESULTS: Seventy-two children between age 0.21 and 15.7 years (boys, n = 35) had isolated amylase deficiency. The highest prevalence of isolated amylase deficiency was found in patients less than 6 months of age (52.9%). From 6 months to 1 year of age, the prevalence was 40%. The prevalence gradually decreased until 18 months. Failure to thrive, poor weight gain, diarrhea, and abdominal bloating were the most frequent indications for ePFT. Eleven children had repeat ePFT after initial diagnosis and 6 had normal enzyme activity, whereas 5 had remained amylase-deficient an average of 1.65 years later. CONCLUSIONS: The prevalence of selective amylase deficiency was 10.1% in the 712 children who underwent ePFT with the suspicion of malabsorption. Low amylase activity is "physiologic" in infants <6 months of age, however, this study supports that it should be considered in the differential diagnosis in children older than 6 months of age.

[DELAYED RESULTS OF ENZYME REPLACEMENT THERAPY, PRESCRIBED BY RESULTS OF 13C-TRIGLYCERIDE BREATH TEST].

Maldigestion persists in most patients with chronic pancreatitis (CP). The objective lipase and amylase insufficiency diagnosis is needed to achieve an adequate clinical response to oral pancreatic enzyme substitution therapy. The novel data is presented in the article about the role of 13C-mixed triglyceride breath test as a tool for exocrine pancreatic insufficiency diagnosis, for evaluating fat malabsorbtion in CP patients. 135 patients were included in the investigation. Delayed results of enzyme replacement therapy were estimated after 1 and 2 year of surveillance. It has been shown, that partial recovery of exocrine pancreatic function is possible, and replacement therapy leads to patients nutritional status improving. Thus 13C-triglyceride breath test could be useful tool in clinical practice for CP diagnosis. The test make it possible to choose the initial pancreatic enzyme dosage and are beneficial during the treatment for pancreatic enzyme dose correction.

[The clinical application of 13C-breath tests in pancreatic diseases].

Maldigestion persists in most patients with chronic pancreatitis (GP). The objective lipase and amylase insufficiency diagnosis is needed to achieve an adequate clinical response to oral pancreatic enzyme substitution therapy. The novel data is presented in the article about the role of 13C-mixed triglyceride and 13C-corn starch breath tests as a tools for exocrine pancreatic insufficiency diagnosis, for evaluating fat and starch malabsorbtion in CP patients. 135 patients were included in the investigation. It has been shown, that 13C-breath tests could be useful tools in clinical practice for CP diagnosis. They are well correlate with fecal elastase-1 level, has high sensitivity and specificity for diagnosis of lipase and amylase deficiency. Tests make it possible to choose the initial pancreatic enzyme dosage and are beneficial during the treatment for pancreatic enzyme dose correction.

Amylase gene silencing by RNA interference improves recombinant hGM-CSF production in rice suspension culture.

A rice cell suspension culture system with the Ramy3D promoter, which is induced by sucrose starvation, has been previously utilized to produce large quantities of recombinant proteins. Although this expression system was reported previously to generate a good yield of recombinant hGM-CSF in transgenic rice cell suspension culture, rice alpha-amylase was a dominant protein, with 43% of total secreted proteins and an obstacle to the production and purification of secreted recombinant proteins in a rice cell suspension culture. In this study, an intron-containing self-complementary hairpin RNA (ihpRNA)-mediated post transcriptional gene silencing (PTGS) strategy for the rice alpha-amylase gene was applied in order to overcome this problem in rice cell suspension culture systems. The reduction of the mRNA level of the rice alpha-amylase gene was verified via Northern blot analysis and siRNA, an initiator of RNA interference, was detected via an RNase protection assay. The amount of rice alpha-amylase in the culture medium was reduced to 8.2% as compared to that of the wild-type. A transgenic rice cell suspension culture expressing both the hGM-CSF and ihpRNA of the rice alpha-amylase gene demonstrated that the quantity of rice alpha-amylase was reduced to 22% and that the accumulation of hGM-CSF increased by 1.9-fold as compared to that in the transgenic cell line expressing hGM-CSF only. These results indicated that RNAi technology should be of great utility for suppressing undesirable genes, and should improve accumulation and facilitate the purification of secreted recombinant proteins in rice cell suspension cultures.

The Shwachman-Bodian-Diamond syndrome gene mutations cause a neonatal form of spondylometaphysial dysplasia (SMD) resembling SMD Sedaghatian type.

The Shwachman-Bodian-Diamond syndrome (SBDS) gene is a causative gene for Shwachman-Diamond syndrome, an autosomal recessive disorder with exocrine pancreatic insufficiency, bone marrow dysfunction and skeletal dysplasia. We report here on two patients with skeletal manifestations at the severest end of the phenotypic spectrum of SBDS mutations. An 11-year-old Japanese girl presented with neonatal respiratory failure necessitating lifelong ventilation support, severe short stature and severe developmental delay. She developed neutropenia in infancy, and decreased serum amylase was noted in childhood. A British boy was a stillbirth with pulmonary hypoplasia and hepatic fibrosis found on autopsy. Both cases had neonatal skeletal manifestations that included platyspondyly, lacy iliac crests and severe metaphysial dysplasia, and thus did not fall in the range of the known Shwachman-Diamond syndrome skeletal phenotype but resembled spondylometaphysial dysplasia (SMD) Sedaghatian type. The girl harboured a recurrent mutation (183TA-->CT) and a novel missense mutation (79T-->C), whereas the boy carried two recurrent mutations (183TA-->CT and 258+2T-->C). We also examined SBDS in one typical case with SMD Sedaghantian type and eight additional cases with neonatal SMD, but failed to discover SBDS mutations. Our experience expands the phenotypic spectrum of SBDS mutations, which, at its severest end, results in severe neonatal SMD.

Mutants of Arabidopsis lacking a chloroplastic isoamylase accumulate phytoglycogen and an abnormal form of amylopectin.

Mutant lines defective for each of the four starch debranching enzyme (DBE) genes (AtISA1, AtISA2, AtISA3, and AtPU1) detected in the nuclear genome of Arabidopsis (Arabidopsis thaliana) were produced and analyzed. Our results indicate that both AtISA1 and AtISA2 are required for the production of a functional isoamylase-type of DBE named Iso1, the major isoamylase activity found in leaves. The absence of Iso1 leads to an 80% decrease in the starch content in both lines and to the accumulation of water-soluble polysaccharides whose structure is similar to glycogen. In addition, the residual amylopectin structure in the corresponding mutant lines displays a strong modification when compared to the wild type, suggesting a direct, rather than an indirect, function of Iso1 during the synthesis of amylopectin. Mutant lines carrying a defect in AtISA3 display a strong starch-excess phenotype at the end of both the light and the dark phases accompanied by a small modification of the amylopectin structure. This result suggests that this isoamylase-type of DBE plays a major role during starch mobilization. The analysis of the Atpu1 single-mutant lines did not lead to a distinctive phenotype. However, Atisa2/Atpu1 double-mutant lines display a 92% decrease in starch content. This suggests that the function of pullulanase partly overlaps that of Iso1, although its implication remains negligible when Iso1 is present within the cell.

Protocolos antienvejecimiento / Antiaging protocols

El autor presenta la necesidad de protocolizar los métodos de diagnóstico y tratamiento con el fin de sistematizar la terapia antienvejecimiento. En relación a los protocolos establecidos, remarca la importancia de valorar, de forma práctica, las distintas pruebas tanto químicas como biológicas: estudio de los componentes sanguíneos, de la composición corporal, el índice de masa corporal o BMl, el índice metabólico basal o BMR, los análisis del colesterol, lipoproteínas, triglicéridos y glucosa y el llamado estado biológico. A continuación expone como Se pueden valorar todos estos datos obtenidos para poder aplicar el correspondiente tratamiento mediante un aporte enzimático (enzimas digestivas, metabólicas y alimentarias), analizando la influencia corporal de los déficits de determinadas enzimas alimentarias (proteasa, amilasa, lipasa, celulasa, etc) así como sus mecanismos y niveles de actuación para finalmente exponer una serie de puntos clave y las diferentes soluciones recomendables para modificar el proceso del envejecimiento con especial énfasis en el ejercicio y sus diversas modalidades (AU)

Isolated pancreatic amylase deficiency: probable error in maturation.

A boy with failure to thrive and isolated pancreatic amylase deficiency is described. Immunoprecipitation confirmed only salivary isoamylase in duodenal fluid at ages 20 and 33 months. Because normal pancreatic amylase messenger RNA was detected by reverse-transcriptase polymerase chain reaction in the fluid, failure of the normal maturation of pancreatic amylase secretion may explain the deficiency.

A starch-accumulating mutant of Arabidopsis thaliana deficient in a chloroplastic starch-hydrolysing enzyme.

The aim of this work was to identify enzymes that participate in the degradation of transitory starch in Arabidopsis. A mutant line was isolated by screening leaves at the end of the night for the presence of starch. The mutant had a higher starch content than the wild-type throughout the diurnal cycle. This accumulation was due to a reduction in starch breakdown, leading to an imbalance between the rates of synthesis and degradation. No reduction in the activity of endo-amylase (alpha-amylase), beta-amylase, starch phosphorylase, maltase, pullulanase or D-enzyme could be detected in crude extracts of leaves of the mutant. However, native PAGE in gels containing amylopectin revealed that a starch-hydrolysing activity, putatively identified as an endo-amylase and present in wild-type chloroplasts, was absent or appreciably reduced in the mutant. This is the first time that a specific enzyme required for starch degradation has been identified in leaves.

Macroamylasemia associated with ulcerative colitis.

We describe a very rare case in which macroamylasemia was associated with ulcerative colitis of total colitis type. The patient's serum amylase isozyme pattern by electrophoresis showed a broad abnormal peak toward the side of the positive pole compared with regular salivary and pancreatic fractions. Sephadex G-200 column chromatography showed a sedimentation coefficient of 6.6 S. Amylase activity was bound to IgG. Double diffusion experiments demonstrated that amylase activity could be precipitated in gel by an antibody to the lambda chain. Although inflammatory bowel disease is occasionally associated with hyperamylasemia due to pancreatitis, we emphasize that, when hyperamylasemia is recognized in patients with inflammatory bowel disease, macroamylasemia also should be considered.

Familial pancreatic enzyme insufficiency.

A father and son with profound reduction of exocrine pancreatic activity and little visible pancreatic tissue on ultrasound or computed tomography are described. Both have some degree of liver disease, which is more marked in the son. The disorder, apparently familial, does not correspond to any reported previously.

[Urinary amylase activity and debit as indices of the functional status of the pancreas and gallbladder]. / Aktivnost' i debit uroamilazy kak pokazateli funktsional'nogo sostoianiia podzheludochnoi zhelezy i zhelchnogo puzyria.

The functional state was studied of the pancreas and gallbladder by calculation of the activity and yield of uroamylase in 96 persons. Data are compared that were obtained on the basis of this method. There was a clear correlation with results obtained during cholecystography. This simple and precise method may be recommended for wide practical use.

Selective deficiency of pancreatic amylase.

Two patients with specific pancreatic amylase deficiency are described. The greatly reduced pancreatic amylase activity was not due to an enzymatically inactive amylase molecule but to an almost complete absence of the molecule itself. The findings are of diagnostic importance as they show that low pancreatic amylase activity in serum or duodenal aspirates, or both, does not necessarily represent chronic exocrine pancreatic disease such as chronic pancreatitis, carcinoma of the pancreas, or cystic fibrosis but may be an isolated finding. In one of our patients a familial occurrence was shown, indicating a congenital deficiency.

[The role of disorders of secretion of pancreatic enzymes and bile and bacterial contamination of the small intestine in the pathogenesis of diarrhea in patients with celiac disease]. / Ro'l narusheniia sekretsii pankreaticheskikh fermentov, zhelchi i bakteria'lnogo obsemeneniia tonkoi kishki v patogeneze diarei u bo'lnykh tseliakiei.

The study of 53 patients with celiac disease provided evidence for the impotent role of the inhibited hyposecretion of pancreatic enzymes, atony of the gallbladder responsible for abnormal bile acids introduction into the intestinal lumen in digestion, elevated concentrations of free bile acids at the expense of lowjugated ones in duodenal and jejunal contents as well as bacterial dissemination of the proximal portion of the small intestine in pathogenesis of diarrhea observed in celiac disease. It is concluded that inclusion of continuous courses of enzyme preparations and light cholagogues in the treatment schemes of celiac disease and administration in its exacerbation of adsorbents, astringents, antibacterial preparations should be necessary therapeutic measures.

Reversal by glucose of pancreatic amylase insufficiency in chronic alcoholic rats.

Carbohydrate consumption regulates pancreatic amylase synthesis in rats. The Lieber-DeCarli 36% alcohol diet employed in chronic alcohol studies and the isocaloric control diet contain 11 and 47% of total calories from carbohydrates, respectively. Young rats fed ad libitum the 36% ethanol diet for 2 weeks obtained 1.2 g/day of carbohydrate, whereas those pair-fed with control diet received 5.8 g/day. Rats fed the 36% ethanol diet and given an intramuscular injection of a solution of 1.5 g of glucose daily for 2 weeks received twofold greater amounts of carbohydrate than saline-injected controls (2.7 versus 1.2 g). These changes in carbohydrate intake produced proportionate changes in pancreatic amylase levels. The secretory responses to cholecystokinin-octapeptide (CCK8) of acini from control and glucose-injected rats were significantly higher compared with those in the saline-injected or noninjected alcohol groups. The blood alcohol levels in glucose-injected rats were markedly reduced compared with other alcohol groups (71.7 versus 274.9 mg/dl) despite similar amounts of ethanol ingestion daily (2.4 g) in the three groups. In vitro experiments with acini from rats fed a nutritionally optimal diet revealed that high pharmacologic concentrations of ethanol, while inducing basal secretion, inhibited CCK8-stimulated amylase secretion. These results indicate that: (a) the amount of alcohol consumption does not correlate with either the levels of blood alcohol or of pancreatic amylase; (b) the carbohydrate availability in rats regulates pancreatic amylase levels despite significant levels of alcohol in blood; (c) blood alcohol levels observed in vivo may not affect synthetic and secretory processes of amylase in pancreatic acini.

Absorption of glucose polymers from canine jejunum deprived of pancreatic amylase.

We evaluated the absorption of glucose polymers in canine jejunal Thiry-Vella fistulas proven to be free of pancreatic amylase. Medium-length oligomers with degrees of polymerization of 6 through 10 glucose units (DP 6-10) and long-chain material (DPavg23) were isolated from a cornstarch hydrolysate. We perfused 90, 180, and 360 mg/dl solutions of glucose, DP 6-10, and DPavg23 at 0.4, 1.9, and 3.4 ml/min. At all perfusion rates carbohydrate absorption decreased as the chain length of the oligomers increased, and these differences persisted even at the slowest perfusion rate employed. In two additional animals the fistulas were perfused at 3.4 ml/min with the three test carbohydrates at concentrations of 90, 180, 225, 270, 315, 360, 405, and 450 mg/dl. At this flow rate, the assimilative process of DP 6-10 and the long-chain fraction appeared to be saturated at carbohydrate concentrations above 360 mg/dl, whereas the absorption of glucose was linearly related to concentration throughout the range studied. With both groups of polymers, the fluid emerging from the fistula was virtually free of glucose, a finding that suggests that polymer digestion, not glucose absorption, is the rate-limiting step for polymer assimilation.

Development of carbohydrate absorption in the fetus and neonate.

Maturation of mechanisms for carbohydrate absorption occurs in a defined sequence during human fetal development. The intestinal enzymes, lactase, sucrase, maltase, isomaltase, and glucoamylase, are at mature levels in the term fetus. Mature levels of pancreatic amylase activity and glucose transport occur postnatally, and levels are low in both the term and preterm neonate. In the preterm infant, sucrase, maltase, and isomaltase are usually fully active, but lactase activity, which increases markedly from 24 to 40 weeks, may be low depending upon fetal age. Despite these developmental patterns, clinical lactose intolerance is uncommon. Postnatal adaptive responses to ingested carbohydrates lead to competent carbohydrate absorption. Inadequately absorbed carbohydrates are salvaged by colonic flora through fermentation of carbohydrates to hydrogen gas and short-chain fatty acids; the latter are readily absorbed by the colon. In this setting, carbohydrate tends to be absent from the stool. Noninvasive reflection of the status of carbohydrate absorption may be obtained from breath hydrogen testing, a technique of particular value in young infants.