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91.
Bendall JK Damy T Ratajczak P Loyer X Monceau V Marty I Milliez P Robidel E Marotte F Samuel JL Heymes C 《Circulation》2004,110(16):2368-2375
92.
Frédéric Carrière Philippe Grandval Christophe Renou Aurélie Palomba Florence Priéri Jacqueline Giallo Friederike Henniges Suntje Sander-Struckmeier René Laugier 《Clinical gastroenterology and hepatology》2005,3(1):28-38
BACKGROUND & AIMS: The contribution of human gastric lipase (HGL) to the overall lipolysis process in chronic pancreatitis (CP), as well as the relative pancreatic enzyme levels, rarely are addressed. This study was designed to quantify pancreatic and extrapancreatic enzyme output, activity, and stability in CP patients vs. healthy volunteers. METHODS: Healthy volunteers (n = 6), mild CP patients (n = 5), and severe (n = 7) CP patients were intubated with gastric and duodenal tubes before the administration of a test meal. HGL, human pancreatic lipase (HPL), chymotrypsin, and amylase concentrations were assessed in gastric and duodenal samples by measuring the respective enzymatic activities. Intragastric and overall lipolysis levels at the angle of Treitz were estimated based on quantitative analysis of lipolysis products. Similar analyses were performed on duodenal contents incubated ex vivo for studying enzyme stability and evolution of lipolysis. RESULTS: Although HPL, chymotrypsin, and amylase outputs all were extremely low, HGL outputs in patients with severe CP (46.8 +/- 31.0 mg) were 3-4-fold higher than in healthy controls (13.3 +/- 13.8 mg). Intragastric lipolysis did not increase, however, in patients with severe CP, probably because of the rapid decrease in the pH level of the gastric contents caused by a higher gastric acid secretion. HGL remains active and highly stable in the acidic duodenal contents of CP patients, and, overall, can achieve a significant lipolysis of the dietary triglycerides (30% of the control values) in the absence of HPL. CONCLUSIONS: Although all pancreatic enzyme secretions are simultaneously reduced in severe CP, gastric lipase can compensate partly for the loss of pancreatic lipase but not normalize overall lipolytic activity. 相似文献
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Van Laethem C Bartunek J Goethals M Nellens P Andries E Vanderheyden M 《American heart journal》2005,149(1):175-180
Background
The oxygen uptake efficiency slope (OUES) is a new submaximal parameter which objectively predicts the maximal exercise capacity in children and healthy subjects. However, the usefulness of OUES in adult patients with and without advanced heart failure remains undetermined. The present study investigates the stability and the usefulness of OUES in adult cardiac patients with and without heart failure.Methods
Forty-five patients with advanced heart failure (group A) and 35 patients with ischemic heart disease but normal left ventricular ejection fraction (group B) performed a maximal exercise test. PeakVO2 and percentage of predicted peakVO2 were markers of maximal exercise capacity, whereas OUES, ventilatory anaerobic threshold (VAT), and slope VE/VCO2 were calculated as parameters of submaximal exercise.Results
Group A patients had lower peakVO2 (P < .001), lower percentage of predicted peakVO2 (P = .001), lower VAT (P < .05), steeper slope VE/VCO2 (P < .001), and lower OUES (P < .02). Within group A, significant differences were found for VAT, slope VE/VCO2, and OUES (all P < .01) between patients with peakVO2 above and below 14 mL O2/kg/min. Of all the submaximal parameters, VAT correlated best with peakVO2 (r =.814, P < .01) followed by OUES/kg (r = .781, P < .01), and slope VE/VCO2 (r = −.492, P < .001). However, VAT could not be determined in 18 (23%) patients.Conclusions
OUES remains stable over the entire exercise duration and is significantly correlated with peakVO2 in adult cardiac patients with and without impaired LVEF. Therefore, OUES could be helpful to assess exercise performance in advanced heart failure patients unable to perform a maximal exercise test. Further studies are needed to confirm our hypothesis. 相似文献95.
Laurence Dangers Jonathan Giovannelli Gilles Mangiapan Mikael Alves Naïke Bigé Jonathan Messika Elise Morawiec Mathilde Neuville Christophe Cracco Gaëtan Béduneau Nicolas Terzi Isabelle Huet Xavier Dhalluin Nathalie Bautin Jean-Jacques Quiot Corinne Appere-de Vecchi Thomas Similowski Cécile Chenivesse 《Chest》2021,159(4):1621-1629
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Cornelia Speich Rita Wegmüller Gary M. Brittenham Christophe Zeder Colin I. Cercamondi Daniela Buhl Andrew M. Prentice Michael B. Zimmermann Diego Moretti 《British journal of haematology》2021,192(1):179-189
We report the first measurements of long‐term iron absorption and loss during iron supplementation in African children using a stable isotope of iron (57Fe). After uniform labelling of body iron with 57Fe, iron absorption is proportional to the rate of decrease in the 57Fe tracer concentration, while iron loss is proportional to the rate of decrease in the 57Fe tracer amount. Anaemic Gambian toddlers were given 2 mg 57Fe orally to equilibrate with total body iron over 8–11 months. After assignment to the positive control arm of the HIGH study, 22 toddlers consumed a micronutrient powder containing 12 mg iron for 12 weeks followed by 12 weeks without iron supplementation. Their daily iron absorption increased 3·8‐fold during the iron supplementation period compared to the control period [median (interquartile range, IQR): 1·00 (0·82; 1·28) mg/day vs. 0·26 (0·22; 0·35) mg/day; P = 0·001]. Unexpectedly, during the supplementation period, daily iron loss also increased by 3·4‐fold [0·75 (0·55; 0·87) mg/day vs. 0·22 (0·19; 0·29) mg/day; P = 0·005]. Consequently, most (~72%) of the absorbed iron was lost during supplementation. Long‐term studies of iron absorption and loss are a promising and accurate method for assessing and quantifying long‐term iron balance and may provide a reference method for evaluating iron intervention programs in vulnerable population groups. This study was registered as ISRCTN 0720906. 相似文献
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