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PubMed1984

[Effect of the content of crude plant protein in feed on the utilization of urea in dairy cattle. 4. Passage of amino acids through the duodenum].

Model investigations carried out by means of a re-entrant method at the duodenum with dairy cows and with energy-equivalent rations (600 EFU cattle/kg DM), which after the supplementation of 11 g urea/kg DM (150 g/animal and day) contained 13.8 (I), 16.7 (II) and 20.2 (III)% crude protein, had the following results: The amino acid profile of the duodenal protein differed from that of the applied rations and was similar to the microbial protein in the rumen. It only changed inconsiderably with the protein level of the ration. There were differences between the amino acids of the feed as to their apparent rate of fermentation in the rumen. Ser, tyr, lys, and leu apparently proved to be most resistent whereas arg, asp, met, ile and phe were apparently fermented for the most part or completely. The passage rate of amino acids at the duodenum related to intake were, from I ... III 126, 102 and 87%. With all rations there were always net losses of some amino acids (his, arg) and net gains (lys, thr, ser, gly, val, met and tyr) at the duodenum in comparison intake. 15N from urea was incorporated into all the amino acids determined in the duodenal protein, most intensively into glu, ser, asp, ile, gly, his and leu. The apparent digestibility of the total amino acids in the intestines was independent of the crude protein level of the rations and reached 69 ... 71% with a deviation range of 59 ... 81% for the individual amino acids.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗
PubMed1985

[Protein and amino acid metabolism in the digestive tract growing young bulls. 1. Flow of bacterial raw protein in the duodenum determined by 2,6-diaminopimelic acid as a marker].

The influence of the composition of the rations on the content of diamino pimelic acid (DAP) and N in the bacteria dry matter and on the flow of bacteria crude protein into the duodenum, determined with DAP as marker, was determined on the basis of experimental investigations with young bulls provided with duodenal cannulae and with 28 different rations whose details are described. At a production level corresponding to dry matter intake and a variation range of the crude fibre content of between 11.3 and 29.1% in the DM, a content of N-free extractives between 50.9 and 77.4% in the DM, a content of soluble carbohydrates ibetween 5.3 and 6.4% in the DM, a crude protein content of between 6.4 and 17.1% in the DM and a pure protein content of between 4.9 and 15.5% in the DM, the DAP content of the bacteria DM amounts the 0.350 g 100 g DM +/- 0.090 the N-content of the bacteria DM amounts to 7.37 +/- 1.08 g/100 g DM, there are no relations between DAP- and N-content in the bacteria DM and the content of the individual carbohydrate fractions of the ration, there are positive relations between DAP- and N-content of the bacteria DM, the flow of bacterial crude protein into the duodenum amounts to 133 +/- 14 g/kg truly fermentable organic matter or 130 +/- 14 g/kg apparently digestible organic matter, there is a negative relation between bacteria crude protein at the duodenum (BCPD)/kg truly fermentable organic matter and the crude fibre content of the ration, there is a positive relation between BCPD/kg truly fermentable organic matter and N-free extractives and soluble carbohydrate content as well as the digestibility of the organic matter of the ration, there is no specific influence of the flow rate (kg digesta/kg intake of org. matter) or the dilution rate (g bacteriafree org. matter D/kg LW075/b) on BCPD/kg truly fermentable org. matter, there is a dependence of BCPD/kg truly fermentable org. matter on crude protein concentration in the ration in the concentration range of 6.4-9.0% crude protein in the ration (provided endogenous CP equivalents are used).

Amino Acids↗
PubMed1985

[Protein and amino acid metabolism in the gastrointestinal tract of young bulls. 3. Flow of NH3-free raw protein into the duodenum].

The amount of NH3-free crude protein getting into the duodenum corrected by the endogenous crude protein quota was determined on the basis of 28 differently composed rations for growing bulls in the live weight range of 140-460 kg provided with duodenal re-entrant cannulae. The experimental results were generalized by means of regression analysis and can be summarized as follows: The amount of NH3-free crude protein getting into the duodenum can partially be calculated with the regression equation (Formula: see text) resp. NH3-free crude protein D = 155 app. dig. org. matter + 0.262 pure protein +/- 42. The remaining dispersion amounts to +/- 6% of the mean value. The coincidence between the values calculated with these equations and those measured experimentally is very good. There is an interaction between the pure protein of feed getting into the duodenum in % of pure protein intake (y) and the bacteria crude protein D/kg app. dig. org. matter (x) characterized by the equation y = 116.8-0.52 x +/- 12.9. The amount of NH3-free crude protein duod. is not influenced by the flow rate (kg digesta/kg intake of org. matter) and not by the "dilution rate' (g bacteria free org. matter duod./kg live weight 0.75/h) either at a DM intake adequate to the production level. Apart from the partial estimation of the NH3-free crude protein duod. a evaluation based on the crude protein and pure protein concentration in app. dig. org. matter of the ration is possible.

Amino Acids↗
PubMedDate not supplied

[Protein and amino acid metabolism in the digestive tract of growing bull calves. 5. The amino acid flow into the duodenum].

The flow of the individual amino acids (AA) into the duodenum was determined after the feeding of 28 different rations to young bulls supplied with duodenal re-entrant cannulae in the live weight range between 140 and 460 kg. The distribution of AA into AA of bacterial origin and AA from the feed was made by difference calculation between the AA at the duodenum (corrected by the endogenous AA quota) and the AA from the bacteria crude protein, with our own results based on a constant AA composition of the bacteria crude protein; by the regression analysis from relative values according to AAD/app. dig. org. m. = a + b AAF/app. dig. org. m. and by the regression analysis of the absolute values according to AAD = b1 app. dig. org. m. + b2 AAF showed the same results from the regression methods but deviating ones from the difference method. The calculation of the flow of the individual AA into the duodenum from the AA content of the ration and the content of app. dig. org. m. of the ration is possible. The equations derived for this purpose of the individual AA are given.

Amino Acids↗
PubMed1986

[Protein and amino acid metabolism in the intestinal tract of growing young bulls. 7. Protein estimation and evaluation of protein supply in growing ruminants by the apparently digestible total protein in the duodenum based on rations].

The following values were derived from experimental studies of the crude protein (CP) and amino acid (AA) metabolism of growing fattening bulls, the detailed results of which were described in installments 1-6, for the ascertainment of the content of apparently digestible total protein at the duodenum (ADTPD): a) partial method: Degradation quotaCP = NPN + 0.69 X g pure protein/CP; g AD feed PD = g CP (1 -decomposition quotaCP) X 0.72 or g AD feed PD = 0.31 X g pure protein X 0.72; g ADBPDE = 0.149 X g AD org. matter X 0.80 X 0.72 (ADBPDE = apparently digestible pure bacteria protein at the duodenum, dependent on energy release in the reticulo-rumen; g ADBPDN = g CP X (degradation quotaCP) X 0.80 X 0.72 (ADBPDN = apparently digestible pure bacteria protein at the duodenum, dependent on CP supply of rumen microbes); g AD total PD = g AD feed PD + ADBPDE g AD total PD = g AD feed PD + ADBPDN; b) summarizing method: AD total PD = 0.429 + 10.9 X 0.80/CP in % AD org. matter X (CP intake) X 0.72; AD total PD = 0.196 + 16.6 X 0.80/pure protein % AD org. m. X pure pr. intake X 0.72. The requirement of AD total PD was calculated under consideration of the endogenous urine N, skin N and hair N losses as well as protein retention per kg live weight assuming a utilization of 0.70 for this partial performance. The practical application of this balance method is demonstrated in comparison to the digestible CP-system.

Amino Acids↗
PubMed2003

Segmental resection of the third portion of the duodenum for a gastrointestinal stromal tumor: a case report.

We describe a case in which segmental resection of the third portion of the duodenum was performed for a gastrointestinal stromal tumor (GIST). A 31-year-old woman was found to have a 3.5 cm hypovascular tumor at the posterior inferior aspect of the pancreatic head. Preoperative duodenal biopsy revealed that the tumor was positive for c-kit and vimentin, and was diagnosed as a duodenal GIST. Segmental resection of the third portion of the duodenum with papilloplasty and duodenojejunostomy was carried out and there were no postoperative complications. Pancreatoduodenectomy is not always necessary in the treatment of a duodenal GIST. This duodenectomy procedure can serve as a less extensive resection for a duodenal GIST located in the third portion of the duodenum.

Adenocarcinoma↗
PubMed1987

Influence of carbachol and isoproterenol on myoelectrical activity of the uterus, vagina, and duodenum in the conscious domestic hen.

The influence of intravenous infusion (20 min) of carbachol (CAR) and isoproterenol (IPN) on myoelectrical activity of the uterus, vagina, and duodenum was studied in 6 conscious and unrestrained hens. IPN infusions (1.5, 7.5, and 15 micrograms/hen/min) were performed before oviposition, and CAR infusions (0.5, 1.5, and 5 micrograms/hen/min) were administered after oviposition. CAR infusions resulted in a significant stimulation of myoelectrical activity of the vagina (1.5 and 5 micrograms/min) and the duodenum (5 micrograms/min), and in a significant increase (45 +/- 6%) in heart rate (HR), as compared to control values. These effects were blocked by previous i.v. injections of atropine (0.4 mg/hen). IPN infusions induced a significant inhibition of myoelectrical activity of the middle (7.5 and 15 micrograms/min) and caudal (all doses) uterine segments, of the vagina (7.5 and 15 micrograms/min), and of the duodenum (15 micrograms/min), and a significant tachycardia (39 +/- 14%) as compared to control values. The inhibitory effects of IPN on all organs studied and the stimulatory action on HR were suppressed by propranolol (0.24 mg/hen). The sensitivity of the vagina to both drugs argues for a more active participation of this oviductal part in the mechanism of oviposition.

Animals↗
PubMed1976

Release of immunoreactive serotonin following acid perfusion of the duodenum.

Cannulas were placed in the portal vein, hepatic vein, and infrarenal vena cava in eight anesthetized dogs. The duodenum of each dog was irrigated with saline (control) and 0.1 N HCI (50 ml in 10 min). Heparinized blood samples were taken from each cannula 5 min before, and 1, 5, 10, 30 and 60 min after each irrigation for measurement of immunoreactive serotonin concentrations. Serotonin concentrations did not change during saline irrigation of the duodenum. In contrast, serotonin release was consistently observed after duodenal acidification (pH 1.5-2.0). Portal venous serotonin concentrations were increased at 1 min (356 +/- 147 ng/ml) and following a biphasic pattern remained elevated at 30 and 60 min (499 +/- 131 and 489 +/- 187 ng/ml, respectively). Concentrations in the hepatic vein rose more slowly and to a lower peak (357 +/- 123 ng/ml at 10 min). Caval serotonin concentrations were increased at 10 min (342 +/- 121 ng/ml) but promptly returned to baseline levels. In the canine gastrointestinal tract, immunoreactive serotonin concentrations were highest in the duodenal bulb (15.4 mug/gm). This study demonstrated serotonin release from the duodenum following acid perfusion and documented that some of the released serotonin escaped hepatic inactivation. These findings support the possibility that serotonin may be a gastrointestinal hormone involved in the feedback inhibition of gastric acid secretion.

Animals↗
PubMed1989

Duodenum-preserving resection of the head of the pancreas in severe chronic pancreatitis. Early and late results.

In 128 patients with severe chronic pancreatitis and inflammatory enlargement of the head of the pancreas, a duodenum-preserving resection of the pancreatic head was performed. Median post-operative hospitalization was 15.5 days, and the frequency of reoperation was 5.5%. One patient died during the early post-operative phase, and hospital mortality amounted to 0.8%. After a median follow-up period of 3.6 years (range of 7 months to 16 years), six of 127 patients died (late mortality of 4.7%). Seventy-seven per cent of the patients were completely free of abdominal pain, 67% returned to their former occupations. During the late follow-up period, the glucose metabolism was unchanged in 80.7% of the patients, in 13.7% it deteriorated, and in 5.5% it improved permanently; 80% of the patients experienced a marked increase in weight averaging 8.7 kg. Compared with the Whipple procedure, the duodenum-preserving resection of the head of the pancreas spares the patient with chronic pancreatitis a gastrectomy, duodenectomy, and resection of the extrahepatic biliary ducts. In terms of a subtotal resection, the limited operative intervention at the head of the pancreas and the preservation of the duodenum explain the low early and late postoperative morbidity and mortality.

Adult↗
PubMed1995

Duodenum-preserving resection of the head of the pancreas in chronic pancreatitis. A prospective, randomized trial.

OBJECTIVE: Two techniques of duodenum-preserving resection of the head of the pancreas were compared in a prospective, randomized trial. The technical feasibility and effects on quality of life were assessed. SUMMARY BACKGROUND DATA: Drainage and resection are the principles of surgery in chronic pancreatitis. The techniques of duodenum-preserving resection of the head of the pancreas as described by Berger and Frey combine both to different degrees. The efficacy of both procedures has not been compared thus far. METHODS: Forty-two patients were allocated randomly to either Beger's (n = 20) or Frey's (n = 22) group. In addition to routine pancreatic diagnostic work-up, a multidimensional psychometric quality-of-life questionnaire and and a pain score were used. Assessment of endocrine and exocrine function included oral glucose tolerance test, serum concentrations of insulin, C-peptide, and HbA1c, as well as fecal chymotrypsin and pancreolauryl test. The interval between symptoms and surgery ranged from 12 months to 12 years, with a mean of 5.7 years. The mean follow-up was 1.5 years. RESULTS: There was no mortality. Overall morbidity was 14% (20% Beger, 9% Frey). Complications from adjacent organs were resolved definitively in 94% (90% Beger, 100% Frey). A decrease of 95% and 94% of the pain score after Beger's and Frey's procedure, respectively, and an increase of 67% of the overall quality-of-life index in both groups were observed. Endocrine and exocrine function did not differ between both groups. CONCLUSIONS: Both techniques of duodenum-preserving resection of the head of the pancreas are equally safe and effective with regard to pain relief, improvement of quality of life, and definitive control of complications affecting adjacent organs. Neither procedure leads to further deterioration of endocrine and exocrine pancreatic function.

Chronic Disease↗
PubMed1977

En bloc transplantation of the liver, pancreas, duodenum, spleen, and kidney in the rat.

Five organs consisting of the liver, pancreas, duodenum, spleen, and kidney from (Lewis X Brown Norway)F1 rats were transplanted simultaneously as an en bloc graft to Lewis recipients. No immunosuppression was given postoperatively. Serial laporatomies were performed for macroscopic examination and biopsies of the grafts. Macroscopically, the first evidence of rejection was splenic enlargement followed by fatty metamorphotic change of the liver, dilation and loss of peristalsis of the duodenum, and injection of the pancreas. The kidney maintained normal color and consistency until late in the rejection process. Histological examination suggested that the liver and the spleen may be more vulnerable to immune attack, since in these organs cellular infiltration started earlier and was more extensive in comparison to other organs. While the pancreas exhibited a typical, although somewhat delayed rejection pattern, the kidney seemed to maintain a well preserved structure. Interestingly, the duodenum showed no significant cellular infiltration throughout the postoperative period of examination despite severe mucosal destruction.

Animals↗
PubMed2004

Displacement of endoscopically placed plastic biliary endoprostheses into the duodenum with a simple transhepatic technique.

The authors to describe the technique and report the results of percutaneous displacement of endoscopically placed plastic biliary endoprostheses into the duodenum at the time of transhepatic intervention in 34 patients. Displacement into the duodenum was effected by simply passing a guide wire through the stent, and then pushing it into the gut with a catheter. Thirty-three of 36 stents (92%) were successfully displaced in this manner. No complications related to stent passage out of the gastrointestinal tract were encountered. Plastic biliary stents can be safely displaced into the duodenum when patients undergo transhepatic biliary procedures, thus avoiding repeated endoscopy.

Adult↗
PubMed1996

Manometric responses of human duodenum during infusion of HCl, hyperosmolar saline, bile and oleic acid.

Duodenal motor activity is incompletely understood. The purpose of this study was to define the contractile patterns of the duodenum that occur in response to rate controlled injection of various solutions. In nine healthy volunteers we placed a six channel perfused catheter, and recorded pressure activity in the antrum, pylorus and duodenum. Volumes of 10 and 20 mL of 0.9% NaCl, 100 mM HCl (pH 1), 5% NaCl (1711 mOsm/kg), human bile and iso-osmolar sodium oleate were randomly injected into the duodenum at 20 ml/min, starting 15 min after phase III migratory motor complex (MMC). A 20 mL bolus of each solution caused more activity (P < 0.05) than a 10 mL bolus, but the motor pattern was similar. The control, 0.9% NaCl, produced occasional pressure waves, whereas bile and sodium oleate induced more (P < 0.05) activity which consisted of low amplitude, isolated or clusters (2-4 cycle/min) of non-propagating pressure waves that occurred at random sites. In three subjects, oleate produced isolated pyloric phasic contractions. In contrast, HCl and 5% NaCl induced high amplitude pressure waves that were seen either at a single channel or at multiple channels, occurring simultaneously. The motility index was also greater (P < 0.05) than that induced by other solutions. Additionally, within 2 min of infusion, a phase III MMC like pattern was observed in five of the nine subjects who received HCl and three of the nine who received 5% NaCl. A non-nutrient iso-osmolar solution induced occasional motor activity. HCl and hyperosmolar solutions induced more frequent and large amplitude, segmental contractions whereas lipid and bile induced fewer and smaller amplitude contractions. The volume, the pH, the osmolar and the nutrient make up of the infusate may each influence the duodenal motor responses.

Adolescent↗
PubMed2004

Effect of Escherichia coli heat-labile enterotoxin on the myoelectric activity of the duodenum in weaned pigs.

The objective of the present study was to elucidate the effect of subclinical doses of Escherichia coli heat-labile enterotoxin (LT) on the antro-duodenal myoelectric activities of weaned pigs. Twelve weaned pigs were surgically implanted with three pairs of electrodes on the antrum 3 cm before the pylorus, 5 and 20 cm after the pylorus on the duodenum, respectively. An infusion cannula was inserted into the duodenum between duodenal electrodes. Using a wireless telemetry recording system, an electromyography (EMG) tracing lasting at least 24 h was recorded as the control, then another 24-h EMG recording was performed with a bolus intraduodenal infusion of LT (0.1 and 0.5 microg/kg b.w.). After a 1- to 2-day break, a 5-fold higher dose of LT was administered using the same protocol. In the antrum, LT administration barely modified the EMG signal. However, in the duodenum it prolonged the duration of phase II and the migrating myoelectric complex (MMC) cycle when compared with the control. The number of duodenal MMC cycles was also significantly diminished. Moreover, the migrating velocity of phase III was increased. The migrating action potential complex (MAPC) was present both without and with LT, but occurred more frequently following LT administration. In conclusion, LT caused a dose-dependent, lagged alteration in the duodenal MMC in weaned pigs, involving a reduction of the MMC number by lengthening phase II, increased phase III migration velocity, and increased MAPC frequency. The disturbances did not, however, result in diarrhoea and may reflect the induction of a local protection mechanism of the gut to expel unwanted foreign content from the lumen of the upper gut.

Animals↗
PubMed1990

Duodenectomy without pancreatectomy for extensive benign villous adenoma of the duodenum.

Villous adenomas of the duodenum are uncommon, but two have been treated recently in Blenheim. One of these was an extensive benign tumour involving most of the second part of the duodenum but causing no biliary tract obstruction. It was treated by pyloric sphincter-sparing duodenectomy without pancreatectomy, with repair by Roux loop to the bile and pancreatic ducts and proximal duodenum. This procedure does not appear to have been described previously.

Adenoma↗
PubMed1996

Evidence that nitric oxide mediates non-adrenergic non-cholinergic relaxation induced by GABA and electrical stimulation in the rat isolated duodenum.

1. GABA (3 x 10(-4) M) and electrical stimulation (60 mV, 1 ms, 0.1 Hz) produced a non-adrenergic non-cholinergic (NANC) relaxation response in the rat isolated duodenum. 2. Tetrodotoxin (10(-6) M) incubation abolished GABA and electrical stimulation responses but not ATP (10(-3) M)-induced relaxation. 3. Desensitization to ATP (10(-3) M) or alpha, beta-methylene ATP (10(-5) M) and incubation with the P1 receptor antagonist 8-phenyltheophylline (10(-5) M) failed to affect relaxation induced by GABA and low frequency electrical stimulation. 4. The inhibitor of L-arginine-NO synthase N omega-Nitro-L-arginine methyl ester (L-NAME) (10(-4)-3 x 10(-4) M) reduced the NANC relaxations elicited by GABA and low frequency electrical stimulation in a dose-dependent manner. These effects were partially reversed by the addition of L-arginine (10(-3)-3 x 10(-3) M). ATP (10(-3) M)-induced relaxations were not modified by L-NAME (3 x 10(-4) M) incubation. 5. These results suggest that nitric oxide is involved in inhibitory NANC transmission in the rat duodenum. We provided original evidence that nitric oxide is involved in neurally mediated relaxations induced by GABA in rat isolated duodenum.

Adenosine Triphosphate↗
PubMed1989

Postnatal changes in response to adenosine and adenine nucleotides in rat duodenum.

1. The effects of adenosine and adenine nucleotides were studied in rat duodenum from postnatal day 1 to day 70. The mechanical activity of duodenal segments was recorded through an isotonic transducer connected to a polygraphic recorder. 2. In rat duodenal segments, adenosine-5'-triphosphate (ATP, 10(-4) M) and adenosine-5'-diphosphate (ADP, 10(-4) M) produced a contractile response on postnatal day 1. This response increased with age, peaking on day 7, followed by a gradual decrease and was non-existent by day 21. In contrast, a relaxant response to ATP and ADP was apparent on day 21, and continued to increase up to day 70. 3. The contraction caused by ATP was inhibited by indomethacin or the P2y-purinoceptor antagonist, reactive blue-2 but not by tetrodotoxin or hyoscine. Thus, it may be mediated by production of prostaglandin through the P2y-purinoceptor. The relaxation produced by ATP was inhibited by reactive blue-2 but not by tetrodotoxin, guanethidine or the P1-purinoceptor antagonist, 8-phenyltheophylline indicating that ATP acts on smooth muscle directly through the P2y-purinoceptor. The pD2 for the contractile response to ATP was 5.15 on day 7 and that for the relaxant response, 6.64 on day 70. 4. Adenosine (10(-4) M) and adenosine-5'-monophosphate (AMP, 10(-4) M) elicited no response before day 14. On day 14, both adenosine and AMP produced a small relaxant response which increased with age. The relaxation produced by adenosine was inhibited by 8-phenyltheophylline but not by tetrodotoxin or guanethidine, indicating that it is mediated by an action on the P1-purinoceptor of smooth muscle. 5. It is evident from these results that in neonatal rat, a contractile response to ATP and ADP occurs initially in the duodenum, followed by a relaxant response to adenosine and AMP on day 14 and to ADP and ATP on day 21. 6. The smooth muscle of rat duodenum may tentatively be concluded to contain separate purinoceptors for adenosine and AMP (Pj) and ADP and ATP (P2) and the responses to P1- and P2-agonists change during the course of development.

Adenine Nucleotides↗
PubMed1990

The ontogeny of purinoceptors in rat urinary bladder and duodenum.

1. The ontogeny of responses to purines and analogues of smooth muscle preparations was studied in rat duodenum and rat urinary bladder. 2. Responses to adenosine and to adenosine 5'-triphosphate (ATP) mediated by P1- and P2-purinoceptors respectively were present as early as postnatal day 2, the earliest day studied. 3. In rat bladder, adenosine was inhibitory and ATP and adenosine 5'-(beta, gamma-methylene) triphosphonate (AMP-PCP) were excitatory, acting on the P2X subtype of P2-purinoceptors. Adenosine was more potent in the neonate than in the adult, while the potency of the nucleotides initially increased with age but then declined, being highest between postnatal days 10 and 25. 4. In rat duodenum also, adenosine was inhibitory, its potency being less than the adult before day 15. 5. ATP at low concentrations was inhibitory in rat duodenum at every age studied and its potency increased with age, but higher concentrations of ATP (3 microM and above) were excitatory until day 15. Both relaxations and contractions were mediated by the P2Y subtype of P2-purinoceptors. These ATP-induced contractions were not inhibited by indomethacin (25 microM) or by tetrodotoxin (1 microM) and are therefore not due to prostaglandin synthesis or to ATP-induced release of transmitter substances from nerves. 6. These results show that responses to adenosine and to adenine nucleotides are present from birth and vary with age, and that the changes seen indicate a differential development for P1-, P2X- and P2Y-purinoceptors.

Aging↗