A comparison of salicylic acid levels in normal subjects after rectal versus oral dosing

ST-Elevation Myocardial Infarction and Non-ST-Elevation Myocardial Infarction: Medical and Surgical Interventions

Coronary artery disease is the leading cause of death in both men and women in the United States. Annually, 790,000 Americans will experience a myocardial infarction. Early recognition and appropriate management of myocardial infarction are imperative to improving patient outcomes. This article discusses the pathophysiology, presentation, and diagnosis and management of both ST-elevation myocardial infarction (STEMI) and non-STEMI.

Pharmacokinetics of Salicylic Acid Following Intravenous and Oral Administration of Sodium Salicylate in Sheep

Simple Summary

Scarcity of non-steroidal anti-inflammatory drugs (NSAID) to minimise the pain in sheep instigated the current study. The aim of this study was to know the pharmacokinetic parameters of salicylic acid in New Zealand sheep after administration of multiple intravenous and oral doses of sodium salicylate (sodium salt of salicylic acid). Results of the study suggest that the half-life of the drug was shorter and clearance was faster after intravenous administration as compared to that of the oral administration. The minimum effective concentration required to produce analgesia in humans (16.8 µL) was achieved in sheep for about 0.17 h in the current study after intravenous administration of 100 and 200 mg/kg body weight of sodium salicylate. However, oral administration of these doses failed to achieve the minimum effective concentration as mentioned above. This study is of significance as it adds valuable information on pharmacokinetics and its variation due to breed, species, age, gender and environmental conditions. As per the authors’ knowledge, this is the only study showing detailed information about absorption, distribution and elimination of salicylic acid in New Zealand Sheep. An intravenous administration of sodium salicylate at 100 and 200 mg/kg dose may produce analgesia in sheep, which requires further investigation using pharmacokinetic–pharmacodynamic (PKPD) integration or modelling techniques.

Abstract

The pharmacokinetics of salicylic acid (SA) in sheep was evaluated following intravenous (IV) and oral administration of sodium salicylate (sodium salt of salicylic acid) at different doses. Six healthy sheep were administered sodium salicylate (SS) IV at doses of 10, 50, 100 and 200 mg/kg body weight and another six sheep were drenched with 100 and 200 mg/kg of SS orally. Both studies were randomised crossover trials. A one-week washout period between each treatment was allowed in both studies. Blood samples were collected at 0, 15, 30 min and 1, 2, 4 and 6 h after IV and oral SS administrations. Plasma SA concentrations were determined using high-performance liquid chromatography (HPLC) with diode array detection method. Pharmacokinetic variables were calculated in a non-compartmental model. The elimination half-life (T_{1/2 el}) of SA after IV administration of 200 mg/kg SS was 1.16 ± 0.32 h. Mean bioavailability of SA was 64%, and mean T_{1/2 el} was 1.90 ± 0.35 h, after 200 mg/kg of oral SS. The minimum plasma SA concentration (16.8 µg/mL) reported to produce analgesia in humans was achieved after IV administration of 100 and 200 mg/kg SS in sheep for about 0.17 h in this study. Experiments on pharmacokinetic–pharmacodynamics modelling are required to determine the actual effective plasma concentration range of SA in sheep.

Simultaneous stent expansion/balloon deflation technique to salvage failed balloon remodeling

Herniation, with possible embolization, of coils into the parent vessel following aneurysm coiling remains a frequent challenge. For this reason, balloon or stent assisted embolization remains an important technique. Despite the use of balloon remodeling, there are occasions where, on deflation of the balloon, some coils, or even the entire coil mass, may migrate. We report the successful use of a simultaneous adjacent stent deployment bailout technique in order to salvage coil prolapse during balloon remodeling in three patients. Case No 1 was a wide neck left internal carotid artery bifurcation aneurysm, measuring 9 mm×7.9 mm×6 mm with a 5 mm neck. Case No 2 was a complex left superior hypophyseal artery aneurysm, measuring 5.3 mm×4 mm×5 mm with a 2.9 mm neck. Case No 3 was a ruptured right posterior communicating artery aneurysm, measuring 4 mm×4 mm×4.5 mm with a 4 mm neck. This technique successfully returned the prolapsed coil mass into the aneurysm sac in all cases without procedural complications. The closed cell design of the Enterprise VRD (Codman and Shurtleff Inc, Raynham, Massachusetts, USA) makes it ideal for this bailout technique, by allowing the use of an 0.021 inch delivery catheter (necessary for simultaneous access) and by avoiding the possibility of an open cell strut getting caught on the deflated balloon. We hope this technique will prove useful to readers who may find themselves in a similar predicament.

Simultaneous stent expansion/balloon deflation technique to salvage failed balloon remodeling

Herniation, with possible embolization, of coils into the parent vessel following aneurysm coiling remains a frequent challenge. For this reason, balloon or stent assisted embolization remains an important technique. Despite the use of balloon remodeling, there are occasions where, on deflation of the balloon, some coils, or even the entire coil mass, may migrate. We report the successful use of a simultaneous adjacent stent deployment bailout technique in order to salvage coil prolapse during balloon remodeling in three patients. Case No 1 was a wide neck left internal carotid artery bifurcation aneurysm, measuring 9 mm×7.9 mm×6 mm with a 5 mm neck. Case No 2 was a complex left superior hypophyseal artery aneurysm, measuring 5.3 mm×4 mm×5 mm with a 2.9 mm neck. Case No 3 was a ruptured right posterior communicating artery aneurysm, measuring 4 mm×4 mm×4.5 mm with a 4 mm neck. This technique successfully returned the prolapsed coil mass into the aneurysm sac in all cases without procedural complications. The closed cell design of the Enterprise VRD (Codman and Shurtleff Inc, Raynham, Massachusetts, USA) makes it ideal for this bailout technique, by allowing the use of an 0.021 inch delivery catheter (necessary for simultaneous access) and by avoiding the possibility of an open cell strut getting caught on the deflated balloon. We hope this technique will prove useful to readers who may find themselves in a similar predicament.

Comparison of three aspirin formulations in human volunteers

INTRODUCTION

The treatment of acute coronary syndrome (ACS) includes the administration of aspirin. Current guidelines recommend chewing aspirin tablets to increase absorption. While this is intuitive, there are scant data supporting this recommendation. The purpose of this study is to assess which of 3 different aspirin formulations is most rapidly absorbed after ingestion.

METHODS

A prospective, open-label, 3-way crossover volunteer study at a tertiary university medical center with human subjects 18 years or older. Fasted subjects were randomly assigned to receive aspirin 1,950 mg as (1) solid aspirin tablets swallowed whole, (2) solid aspirin tablet chewed then swallowed, or (3) a chewable aspirin formulation chewed and swallowed. Serum salicylate measurements were obtained over a period of 180 minutes. Pharmacokinetic parameters were determined.

RESULTS

Thirteen males and 1 female completed all 3 arms of study. Peak serum salicylate concentrations were seen at 180 minutes in all groups. Mean peaks were 10.4, 11.3, and 12.2 mg/dL in groups 1, 2, and 3, respectively. Mean area under the time concentration was 1,153, 1,401, and 1,743 mg-min/dL in groups 1, 2, and 3, respectively. No measurable salicylate concentrations were seen in 6 subjects in group 1 at 60 minutes as compared to 1 subject in group 2. All subjects in group 3 had measurable levels at 45 minutes. There were no adverse effects in any of the subjects during the study period.

CONCLUSION

Our data demonstrate that the chewable aspirin formulation achieved the most rapid rate of absorption. In addition, the chewable formulation absorption was more complete than the other formulations at 180 minutes. These data suggest that in the treatment of ACS, a chewable aspirin formulation may be preferable to solid tablet aspirin, either chewed or swallowed.

Intra-Laboratory Pre-Validation of a Human Cell Based in vitro Angiogenesis Assay for Testing Angiogenesis Modulators

The developed standardized human cell based in vitro angiogenesis assay was intra-laboratory pre-validated to verify that the method is reliable and relevant for routine testing of modulators of angiogenesis, e.g., pharmaceuticals and industrial chemicals. This assay is based on the earlier published method but it was improved and shown to be more sensitive and rapid than the previous assay. The performance of the assay was assessed by using six reference chemicals, which are widely used pharmaceuticals that inhibit angiogenesis: acetyl salicylic acid, erlotinib, 2-methoxyestradiol, levamisole, thalidomide, and anti-vascular endothelial growth factor. In the intra-laboratory pre-validation, the sensitivity of the assay (upper and lower limits of detection and linearity of response in tubule formation), batch to batch variation in tubule formation between different Master cell bank batches, and precision as well as the reliability of the assay (reproducibility and repeatability) were tested. The pre-set acceptance criteria for the intra-laboratory pre-validation study were met. The relevance of the assay in man was investigated by comparing the effects of reference chemicals and their concentrations to the published human data. The comparison showed a good concordance, which indicates that this human cell based angiogenesis model predicts well the effects in man and has the potential to be used to supplement and/or replace of animal tests.