Determination of aspirin and salicylic acid in uremic patients' plasma using reversed-phase high-performance liquid chromatography

A simple, rapid, and sensitive method for the determination of aspirin and salicylic acid in plasma of uremic patients is reported. After extraction with hexane, aspirin (ASA) and salicylic acid (SA) were quantified by high-performance liquid chromatography (HPLC) with ultraviolet detection at 229 nm. ASA and SA concentrations and peak-height ratios were linearly related up to 20 micrograms/ml. The lower limit of sensitivity was 0.1 microgram/ml for both compounds. The average recoveries of aspirin and salicylic acid were 27 and 54%, respectively. This procedure offers better performance than do previously described methods. The sample clean-up allows quantitation of a low concentration of aspirin in uremic patients' plasma, commonly rich in interfering endogenous substances.     

Profile of Cytokines in Synovial Fluid Specimens from Patients with Arthritis. Interleukin 8 (IL-8) and IL-6 Correlate with Inflammatory Arthritides

The synovial fluid aspirated from patients with symptomatic arthritis was analyzed for the presence of tumor necrosis factor (TNF), interleukin 6 (IL-6) and interleukin 8 (IL-8). All three cytokines were found in both inflammatory and non-inflammatory arthritides: IL-8 levels ranged from less than 20 to 38,990 pg/ml, IL-6 from less than 10 to 72,300 pg/ml and TNF from less than 4 to 61 pg/ml. No inhibitors of cytokine activity were found. IL-8 and IL-6 were present in significantly higher levels in patients with inflammatory arthritis compared to patients with osteoarthritis, and there was significant correlation between the IL-6 and IL-8 levels. These findings document the presence of multiple cytokines in the synovial fluid specimens of patients with arthritis, and demonstrate that higher cytokine levels accompany inflammatory arthritis.     

Combined tool approach is 100% successful for emergency football face mask removal.

OBJECTIVE: To compare effectiveness of two techniques for removing football face masks: cutting loop straps [cutting tool: FMXtractor (FMX)] or removing screws with a cordless screwdriver and using the FMXtractor as needed for failed removals [combined tool (CT)]. Null hypotheses: no differences in face mask removal success, removal time or difficulty between techniques or helmet characteristics. DESIGN: Retrospective, cross-sectional. SETTING: NOCSAE-certified helmet reconditioning plants. PARTICIPANTS: 600 used high school helmets. INTERVENTIONS: Face mask removal attempted with two techniques. MAIN OUTCOME MEASUREMENTS: Success, removal time, rating of perceived exertion (RPE). RESULTS: Both techniques were effective [CT 100% (300/300); FMX 99.4% (298/300)]. Use of the backup FMXtractor in CT trials was required in 19% of trials. There was significantly (P<0.001) less call for the backup tool in helmets with silver screws (6%) than in helmets with other screws (31%). Mean removal time was 44.51+/-18.79s (CT: 37.84+/-15.37s, FMX: 51.21+/-19.54s; P<0.001). RPE was different between techniques (CT: 1.83+/-1.20, FMX: 3.11+/-1.27; P<0.001). Removal from helmets with silver screws was faster (Silver=33.38+/-11.03, Others=42.18+/-17.64; P<0.001) and easier (Silver=1.42+/-0.89, Other=2.23+/-1.33; P<0.001). CONCLUSIONS: CT was faster and easier than FMX. Most CT trials were completed with the screwdriver alone; helmets with silver screws had 94% screwdriver success. Clinically, these findings are important because this and other research shows that compared to removal with cutting tools, screwdriver removal decreases time, difficulty and helmet movement (reducing potential for iatrogenic injury). The combined-tool approach captures benefits of the screwdriver while offering a contingency for screw removal failure. Teams should use degradation-resistant screws. CLINICAL RELEVANCE: Sports medicine professionals must be prepared with appropriate tools and techniques to efficiently remove the face mask from an injured football player's helmet.     

Bilateral complete discoid medial meniscus combined with posterior cyst formation

Bilateral discoid medial menisci is an extremely rare condition of the knee and it can be associated to other pathological findings, including anterior portion cyst formation. We report on the clinical features, radiographic findings, treatment and results of one patient who presented a bilateral medial discoid meniscus combined with posterior portion cyst of the left knee. To the best of the author’s knowledge, this is the first case of bilateral medial discoid meniscus associated with posterior portion cyst formation.     

Antisense knockdown of the Shaker-like Kv1.1 gene abolishes the central stimulatory effects of amphetamines in mice and rats.

Amphetamine (AMPH) is an indirect sympathomimetic compound classified as a substrate-type releaser that distinguishes it from other stimulants that act as uptake 1 blockers, such as cocaine (COC). In mammals, AMPH elicits central stimulation, hypermotility, anorexia, analgesia and analeptic activity, mainly through the increase of extracellular brain dopamine (DA). The inversion of vesicular transporters and/or intravesicular alkalinization is assumed to have a role in AMPH-induced exocytosis. However, the action mechanism of this compound has not yet been completely clarified. Recent evidence on the action of AMPHs indicates potassium channel-blocking properties in peripheral tissues. We investigated the possible involvement of a Shaker-like Kv1.1 channel subtype in the central effects of AMPH, using an antisense oligodeoxyribonucleotide (aODN) that specifically and reversibly inhibits the expression of these channels in the brain. The effect of aODN pretreatments was studied by evaluating the modification of behavioral effects induced in mice through the intracerebroventricular administration of AMPH, COC, or other compounds. The aODN in mice almost completely blocked the stimulatory effects of AMPH and other releasers but was ineffective in reducing the central activity of COC. In aODN-pretreated rats a strong reduction of the AMPH, but not of the COC-stimulated DA efflux from nucleus accumbens was observed. Our results suggest that the stimulant effects of AMPH and chemically related compounds, but not COC, require the presence of functionally active Kv1.1 channels in the brain.     

The Risk of Myocardial Infarction Associated with Antihypertensive Drug Treatment in Persons with Uncomplicated Essential Hypertension

We conducted a case-control study based on computer-recorded information accrued in the United Kingdom General Practice Research Database to assess and compare the relation between different antihypertensive drug therapies and myocardial infarction in patients with no known clinical or laboratory risk factors for myocardial infarction other than hypertension. Cases were treated hypertensive patients with no other known risk factors who developed a first acute myocardial infarction between January 1, 1993, and October 31, 1994. They were ascertained from a review of the clinical record together with a questionnaire filled out by the attending general practitioner. Controls were matched to each case for age, sex, general practice, and index date. Antihypertensive therapy was derived from the computerized patient record. The study consisted of 210 cases and 793 controls. Compared with users of β-blockers alone, the adjusted relative risk (RR) estimates for all other treatment regimens were close to 1.0. A comparison of users of calcium channel blockers alone with users of β-blockers alone yielded a RR estimate of 0.9 (95% CI 0.5, 1.7). We conclude that the risk of acute myocardial infarction in otherwise healthy, treated hypertensive patients is not materially associated with the particular drug they receive.