Modulation of esophageal peristalsis by alterations of body position

Previous studies have demonstrated that nonviscous liquids traverse the esophagus more rapidly with the subject in the upright rather than the supine position. Conversely, similar studies have shown that viscous liquids traverse the esophagus at similar rates for both upright and supine positions. Our purpose was to define the motor correlates of these differing responses. Six normal volunteers were studied with an infused catheter system incorpoating a Dent sleeve for monitoring lower esophageal sphincter pressure. The subjects were given a series of swallows of a water and a viscous (52 centipoise) bolus in both the supine and upright positions. In the upright position, the water bolus caused an increased velocity of propagation in the proximal esophageal segment that was associated with a shortening of lower esophageal sphincter relaxation time and reductions in amplitude and duration of contraction. No significant changes in the peristaltic wave were noted with the viscous bolus during alterations of body position. We conclude that the more rapid transit of a nonviscous water bolus through the esophagus in the upright position is reflected in specific alterations of esophageal peristaltic parameters. The possible mechanisms for these differing responses are discussed.     

A computational technique for prediction of the number of microscopically visible phagosomes from data on uptake of radiolabeled outer segment material.

A program for a programmable calculator is described which can predict the number of microscopically visible phagosomes at various times given data on the rate of uptake of radiolabeled outer segment material at these times. The phagosomes are assumed to be digested such that the number of visible phagosomes decays exponentially. The half-life of this decay can be varied in the calculations, and the results can be compared with actual phagosome counts.     

A study of the effect of aspirin on the pharmacokinetics of oral and intravenous diclofenac sodium

Summary Previous studies have shown that aspirin interacts with orally administered diclofenac sodium, causing reduced peak concentrations, lower levels and decreased areas under curves. In this study, diclofenac sodium was administered orally and intravenously with and without aspirin, to 6 healthy female volunteers. After intravenous dosing both plasma levels and areas under curves were significantly reduced although none of the rate constants was affected. The volume of distribution of diclofenac was increased as was the plasma clearance. Oral administration with aspirin also resulted in lower plasma levels, particularly peak levels, and areas under curves. Comparison of AUC's for both modes of administration with and without aspirin suggested that lower levels after oral administration were not due to impaired absorption. These observations are best explained by decreased protein binding and increased biliary excretion of diclofenac in the presence of salicylate.     

A pocket calculator program to evaluate confidence limits for the relative risk

A program for the TI-59 calculator is given which calculates confidence limits for the relative risk. Figures giving measures of timing and accuracy are presented.     

A pocket calculator program to fit first order kinetic curves

A program is presented for use with a TI59 calculator in analysing kinetic data, such as that obtained in studying the accumulation or disappearance of biological substances with time. It fits the data to an equation of the form y = a ? be^?kl and yields values of a, b, k and the half-life.     

The fate of a large bolus of exogenous estrogen administered to postmenopausal women

Seventeen postmenopausal women were given a bolus of conjugated estrogens (USP, Premarin®), 17β-estradiol and estriol orally, intravenously or by pellet implantation, and circulating levels of estrone, estradiol and/or estriol were measured by radioimmunoassay at various intervals during a 48–72-h period. Oral administration resulted in a marked rise in serum estrone; parenteral administration resulted in a marked increase in serum estradiol. There was no significant fall in serum gonadotropins during this period. Following estriol administration orally, there was a decided elevation in estriol levels but minimal change in estrone and estradiol.     

MILK FAT BOLUS OBSTRUCTION IN A PRETERM INFANT

ABSTRACT. We describe a preterm infant who developed an intestinal fat bolus obstruction on the 18th day of life. Shortly before the obstruction the infant's feeding had been changed from maternal breast milk to a special formula for preterm infants. Although the fatty acid composition of the bolus resembled breast milk more than the formula, the abrupt change in the feed may have caused the formation of the bolus.     

Postprandial transduodenal bolus transport is regulated by complex peristaltic sequence

INTRODUCTION The spatial and temporal organization of gastrointestinal contraction waves seems to be a more important determinant of the flow of luminal contents than their number and amplitude[1,2]. Therefore, significant advances in understanding intest…     

Long‐term mortality after bolus‐only administration of abciximab,eptifibatide, or tirofiban during percutaneous coronary intervention

Objective:

To evaluate the long‐term mortality after bolus‐only administration of abciximab, eptifibatide, and tirofiban during percutaneous coronary intervention (PCI).

Background:

Studies on platelet glycoprotein IIb/IIIa receptor inhibitors (GPI) administered as bolus‐only during PCI suggest that this strategy may be similar in efficacy, safer, and more cost‐effective compared to a bolus plus infusion of GPI.

Methods:

We evaluated 864 patients (abciximab = 274, eptifibatide = 361, and tirofiban = 229) who underwent PCI with a bolus‐only regimen during January 2003 to August 2005.

Results:

After a median follow up of four (interquartile range, 3–4.5) years, there were a total of 95 (11%) deaths. The survival rate was 83% in the abciximab group, 91% in the eptifibatide group, and 93% in the tirofiban group (P = 0.003 by log‐rank test). After adjustment for baseline clinical and procedural characteristics using a Cox proportional hazards model, the abciximab group had a significantly higher mortality compared to the eptifibatide group (P = 0.003; Hazard ratio (HR) for eptifibatide compared to abciximab was 0.49 (95% confidence intervals [CI]: 0.30–0.78). The long‐term mortality was not significantly different in the tirofiban group compared to the abciximab group (P = 0.33) or the eptifibatide group (P = 0.20), perhaps because of shorter follow‐up period and fewer patients in the tirofiban group.

Conclusion:

When given as bolus‐only during PCI, eptifibatide may improve long‐term survival compared to abciximab. © 2009 Wiley‐Liss, Inc.