46 research outputs found
Effect of aliskiren on post-discharge outcomes among diabetic and non-diabetic patients hospitalized for heart failure: insights from the ASTRONAUT trial
Aims The objective of the Aliskiren Trial on Acute Heart Failure Outcomes (ASTRONAUT) was to determine whether aliskiren, a direct renin inhibitor, would improve post-discharge outcomes in patients with hospitalization for heart failure (HHF) with reduced ejection fraction. Pre-specified subgroup analyses suggested potential heterogeneity in post-discharge outcomes with aliskiren in patients with and without baseline diabetes mellitus (DM). Methods and results ASTRONAUT included 953 patients without DM (aliskiren 489; placebo 464) and 662 patients with DM (aliskiren 319; placebo 343) (as reported by study investigators). Study endpoints included the first occurrence of cardiovascular death or HHF within 6 and 12 months, all-cause death within 6 and 12 months, and change from baseline in N-terminal pro-B-type natriuretic peptide (NT-proBNP) at 1, 6, and 12 months. Data regarding risk of hyperkalaemia, renal impairment, and hypotension, and changes in additional serum biomarkers were collected. The effect of aliskiren on cardiovascular death or HHF within 6 months (primary endpoint) did not significantly differ by baseline DM status (P = 0.08 for interaction), but reached statistical significance at 12 months (non-DM: HR: 0.80, 95% CI: 0.64-0.99; DM: HR: 1.16, 95% CI: 0.91-1.47; P = 0.03 for interaction). Risk of 12-month all-cause death with aliskiren significantly differed by the presence of baseline DM (non-DM: HR: 0.69, 95% CI: 0.50-0.94; DM: HR: 1.64, 95% CI: 1.15-2.33; P < 0.01 for interaction). Among non-diabetics, aliskiren significantly reduced NT-proBNP through 6 months and plasma troponin I and aldosterone through 12 months, as compared to placebo. Among diabetic patients, aliskiren reduced plasma troponin I and aldosterone relative to placebo through 1 month only. There was a trend towards differing risk of post-baseline potassium ≥6 mmol/L with aliskiren by underlying DM status (non-DM: HR: 1.17, 95% CI: 0.71-1.93; DM: HR: 2.39, 95% CI: 1.30-4.42; P = 0.07 for interaction). Conclusion This pre-specified subgroup analysis from the ASTRONAUT trial generates the hypothesis that the addition of aliskiren to standard HHF therapy in non-diabetic patients is generally well-tolerated and improves post-discharge outcomes and biomarker profiles. In contrast, diabetic patients receiving aliskiren appear to have worse post-discharge outcomes. Future prospective investigations are needed to confirm potential benefits of renin inhibition in a large cohort of HHF patients without D
Advances in fault modelling and test pattern generation for CMOS
ISBN: 0818607351MOS technology has specific fault mechanisms which induce specific behaviors when CMOS devices are considered. Stuck-on and stuck-open faults may convert a logical combinational network into an analog and sequential one. It is shown how to perform logic testing in the presence of these faults. Basic theorems for CMOS testing are derived
Test device for a combinatorial logic circuit and integrated circuit including such a device
US4789821 (A1) ; JP62217170 (A) ; FR2592957 (A1) ; EP0229433 (B1)This device and method for testing a combinative logic circuit (4), includes on the one hand a circuit generating test sequences (30) for applying test logic signals to N inputs of the combinative logic circuit and, on the other hand, an output circuit (5) to analyze the output signals of the combinative logic circuit. These test sequences are successively applied to each of the N inputs (E1, E2, E3 and E4) so that an alternating series, at least twice, of logic "1"'s and of logic "0"'s while a word of N-1 bits is applied to the other inputs to ensure the transmission of the said alternating series to the output of the combinative logic circuit
Testing CMOS: a challenge
ISSN: 0279-2834CMOS technology poses a multi-faceted challenge in testing. Since 1978, researchers have recognized that the stuck-open transistor fault requires special test procedures. Other faults, such as transistors stuck-on or shorted, likewise involve complications. However, these fault types have received comparatively little attention. This article reviews results on the testing of stuck-open faults, develops procedures for testing stuck-on faults, and discusses problems in testing for short faults. Through this analysis, the authors arrive at recommendations for investigating `design for CMOS testability'
CCK-1 and CCK-2 receptors regulate gastric pepsinogen secretion
The present study investigated (1) the pharmacological profile of cholecystokinin (CCK) receptor subtypes involved in the regulation of gastric pepsinogen secretion, (2) the influence of gastric acidity on peptic responses induced by CCK-8-sulfate (CCK-8S) or gastrin-I; and (3) the mechanisms accounting for the effects of CCK-like peptides on pepsinogen secretion. In anaesthetized rats, i.v. injection of CCK-8S or gastrin-I increased both pepsinogen and acid secretion. The pepsigogue effect of CCK-8S was higher than that of gastrin-I, whereas acid hypersecretion after CCK-8S was lower than that induced by gastrin-I. Peptic output following CCK-8S was partly blocked by i.v. injection of the CCK1 receptor antagonist, devazepide (-75.3%), or the CCK2 receptor antagonist, L-365,260 [3R(+)-N-(2,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepine-3 yl)-N'-(3-methyl-phenyl)urea; -27.9%], but was fully prevented by combined administration of devazepide and L-365,260. The gastric acid hypersecretory effect of CCK-8S was enhanced by devazepide (+84.5%) and blocked by L-365,260. In contrast, the gastric secretory actions of gastrin-I were insensitive to devazepide, but abolished by L-365,260. Excitatory effects of CCK-8S and gastrin-I were not modified by vagotomy or atropine, whereas cimetidine or alpha-fluoromethylhistidine (irreversible blocker of histidine decarboxylase) partly prevented acid hypersecretion induced by both peptides without affecting their pepsigogue effects. After pretreatment with omeprazole, both CCK-8S and gastrin-I failed to stimulate acid secretion, while they increased pepsinogen output. In rats with gastric perfusion of acid solutions, CCK-8S or gastrin-I increased peptic output in a pH-independent manner either with or without pretreatment with omeprazole. Ablation of capsaicin-sensitive sensory nerves as well as application of lidocaine to the gastric mucosa failed to modify the excitatory effects of CCK-8S or gastrin-I on pepsinogen and acid secretion. Blockade of the nitric oxide (NO) synthase pathway by N(G)-nitro-L-arginine-methyl ester prevented the pepsigogue actions of both CCK-8S and gastrin-I (-61.8% and -71.7%, respectively), without affecting the concomitant increase in acid output. In addition, both these peptides significantly increased the release of NO breakdown products into the gastric lumen. The present results suggest that: (1) both CCK1 and CCK2 receptors mediate the peptic secretory responses induced by CCK-like peptides; (2) the excitatory inputs of CCK-8S and gastrin-I to chief cells are not driven through acid-dependent mechanisms or capsaicin-sensitive afferent sensory nerves; and (3) under in vivo conditions, the stimulant actions of CCK-like peptides on pepsinogen secretion are mediated, at least in part, by an increase in NO generation
CCK-1 and CCK-2 receptors regulate gastric pepsinogen secretion
The present study investigated (1) the pharmacological profile of cholecystokinin (CCK) receptor subtypes involved in the regulation of gastric pepsinogen secretion, (2) the influence of gastric acidity on peptic responses induced by CCK-8-sulfate (CCK-8S) or gastrin-I; and (3) the mechanisms accounting for the effects of CCK-like peptides on pepsinogen secretion. In anaesthetized rats, i.v. injection of CCK-8S or gastrin-I increased both pepsinogen and acid secretion. The pepsigogue effect of CCK-8S was higher than that of gastrin-I, whereas acid hypersecretion after CCK-8S was lower than that induced by gastrin-I. Peptic output following CCK-8S was partly blocked by i.v. injection of the CCK1 receptor antagonist, devazepide (-75.3%), or the CCK2 receptor antagonist, L-365,260 [3R(+)-N-(2,3-dihydro-1-methyl-2-oxo-5-phenyl-1H-1,4-benzodiazepine-3 yl)-N'-(3-methyl-phenyl)urea; -27.9%], but was fully prevented by combined administration of devazepide and L-365,260. The gastric acid hypersecretory effect of CCK-8S was enhanced by devazepide (+84.5%) and blocked by L-365,260. In contrast, the gastric secretory actions of gastrin-I were insensitive to devazepide, but abolished by L-365,260. Excitatory effects of CCK-8S and gastrin-I were not modified by vagotomy or atropine, whereas cimetidine or alpha-fluoromethylhistidine (irreversible blocker of histidine decarboxylase) partly prevented acid hypersecretion induced by both peptides without affecting their pepsigogue effects. After pretreatment with omeprazole, both CCK-8S and gastrin-I failed to stimulate acid secretion, while they increased pepsinogen output. In rats with gastric perfusion of acid solutions, CCK-8S or gastrin-I increased peptic output in a pH-independent manner either with or without pretreatment with omeprazole. Ablation of capsaicin-sensitive sensory nerves as well as application of lidocaine to the gastric mucosa failed to modify the excitatory effects of CCK-8S or gastrin-I on pepsinogen and acid secretion. Blockade of the nitric oxide (NO) synthase pathway by N(G)-nitro-L-arginine-methyl ester prevented the pepsigogue actions of both CCK-8S and gastrin-I (-61.8% and -71.7%, respectively), without affecting the concomitant increase in acid output. In addition, both these peptides significantly increased the release of NO breakdown products into the gastric lumen. The present results suggest that: (1) both CCK1 and CCK2 receptors mediate the peptic secretory responses induced by CCK-like peptides; (2) the excitatory inputs of CCK-8S and gastrin-I to chief cells are not driven through acid-dependent mechanisms or capsaicin-sensitive afferent sensory nerves; and (3) under in vivo conditions, the stimulant actions of CCK-like peptides on pepsinogen secretion are mediated, at least in part, by an increase in NO generation
Peripheral cholecystokinin A and cholecystokinin B receptors mediate stimulation of gastric pepsinogen and acid secretion following intracerebroventricular injection of cholecystokinin-8-sulphate.
BACKGROUND:
Peptides of cholecystokinin family regulate various physiological actions by acting at level of central nervous system.
AIMS:
To: 1) investigate possible influence of central cholecystokinin pathways on gastric pepsinogen and acid secretions; 2) characterize pharmacological profile and location of cholecystokinin receptor subtypes involved in gastric effects of centrally applied cholecystokinin-8-sulphate (cholecystokinin-8S).
METHODS:
Urethane-anaesthetized rats were subjected to continuous perfusion of gastric lumen. Pepsin levels in perfusate were determined by enzymatic assay based on spectrophotometric measurement of products generated by peptic digestion of bovine haemoglobin. Acidity was measured by automatic potentiometric titration of hydrogen ions.
RESULTS:
Following intracerebroventricular injection, cholecystokinin-8S increased both pepsinogen and acid output. In addition, intravenous cholecystokinin-8S stimulated peptic and acid secretions more promptly and at lower doses than after central injection. Stimulant effects of centrally applied cholecystokinin-8S were not affected by intracerebroventricular injection of devazepide (cholecystokinin A receptor antagonist) or L-365,260 (cholecystokinin B receptor antagonist) or by bilateral vagotomy. However, intravenous devazepide partly antagonized pepsigogue action of intracerebroventricular cholecystokinin-8S without affecting its acid hypersecretory effect, whereas after intravenous injection of L-365,260 peptic hypersecretion evoked by intracerebroventricular cholecystokinin-8S was partially prevented and acid response was completely blocked. Similar effects were exerted by intravenous devazepide and L-365,260 against intravenous cholecystokinin-8S. A complete blockade of pepsigogue effects induced by intracerebroventricular or intravenous cholecystokinin-8S was obtained after combined intravenous treatment with devazepide plus L-365,260. Gastric hypersecretory effects of intravenous cholecystokinin-8S were not modified by bilateral vagotomy.
CONCLUSIONS:
Increase in pepsinogen output evoked by centrally applied cholecystokinin-8S does not depend on interaction with central nervous sites. Following central or parenteral injection of cholecystokinin-8S, increase in peptic secretion would result from activation of both peripheral cholecystokinin A and B receptors presumably located at the level of gastric mucosa