Biomedical subjects

P J Sharkey

Publications and source records attributed to P J Sharkey.

5 recordsLinked to original sources

PubMed1998

Designing an incentive based health promotion program.

1. A health incentive program can be an effective intervention for reducing employee population risk and altering health care utilization patterns. 2. An incentive based health promotion program rewards employees for performing a selected set of behaviors. 3. Collecting supporting data (benchmarking, needs assessment, organization data, published data) provides the foundation for the health incentive program design. 4. Choose an incentive appropriate to the employee population and worksite culture.

Benchmarking↗

PubMed1987

Efficacy, safety, hemodynamic effects, and pharmacokinetics of high-dose moricizine during short- and long-term therapy.

Moricizine, 15 mg/kg, was given to 10 patients with frequent ventricular ectopic depolarizations, eight of whom had previously been treated unsuccessfully with antiarrhythmic drugs. A single-blind inpatient study was followed by therapy for up to 6 months. Two patients developed aggravation of arrhythmia during inpatient therapy. Of the eight patients who completed the inpatient study, seven achieved greater than or equal to 80% suppression of total ventricular ectopic depolarizations (P less than 0.001). During inpatient therapy the mean of the individual patients' suppression of total ventricular ectopic depolarizations was 87.9%, paired ventricular beats 99.3%, nonsustained ventricular tachycardia 99.6%, and premature atrial contractions 89.0%. Suppression was maintained during long-term therapy. The PR interval increased 27% (P less than 0.001), QRS interval increased 10% (P less than 0.0001), QTc increased 1% (P not significant), and JTc decreased 2% (P not significant). Heart rate, blood pressure, and left ventricular performance at rest and exercise were unchanged by moricizine. Moricizine half-life was 9.2 +/- 3.4 hours. Plasma levels of moricizine decreased after 10 days of therapy, suggesting induction of metabolic enzyme systems.

Adult↗

PubMed1987

Intravenous verapamil for treatment of multifocal atrial tachycardia with and without calcium pretreatment.

Verapamil was given to 16 consecutive patients with multifocal atrial tachycardia. Intravenous verapamil was administered at a rate of up to 1 mg/min while heart rate and systolic blood pressure were being monitored. The final 5 patients received 1 g of intravenous calcium gluconate 5 minutes before treatment with verapamil; the first 11 received no calcium. The mean +/- SD heart rate decreased by 21% from 129 to 101 beats/min, a difference of 28, 95% confidence interval (CI), 18 to 38 (p less than 0.0005 by t-test), after a mean of 22 +/- 13 minutes from the start of verapamil administration. The mean verapamil dose was 17 +/- 7 mg (6 to 30 mg). Sinus rhythm was restored in 8 patients. Pretreatment with calcium did not block the effect of verapamil on heart rate (27% decrease with calcium compared with 19% decrease without calcium, a difference of 8%, 95% CI, -7 to 23; p = 0.29) but minimized the decrease in systolic pressure (11% decrease with calcium compared with 27% decrease without calcium, a difference of 16%, 95% CI, 7 to 27; p less than 0.01). Verapamil caused transient asymptomatic hypotension in 1 patient. Arterial blood gases were unchanged by verapamil. Thus, verapamil is safe and effective therapy for multifocal atrial tachycardia, consistently slowing the heart rate and often restoring sinus rhythm. Calcium pretreatment may reduce drug-induced hypotension without preventing the antiarrhythmic effect.

Aged↗

PubMed1977

Nutrition of a developing legume fruit: functional economy in terms of carbon, nitrogen, water.

The economy of functioning of the developing fruit of white lupin (Lupinus albus L.) is assessed quantitatively in relation to intake and usage of carbon, nitrogen, and water. Of every 100 units of carbon imported from the parent plant, 52 are incorporated into seeds, 37 into nonmobilizable material of the pod, and the remaining 11 lost as CO(2) to the atmosphere. An illuminated fruit can make net gains of CO(2) from the atmosphere during the photoperiods of all but the last 2 weeks of its life, suggesting that it is active in assimilation of CO(2) respired from pods and seeds. This conservation activity is important to carbon economy.Phloem supplies 98% of the fruit's carbon and 89% of its nitrogen. Most of the xylem's contribution enters early in development. Xylem and phloem supply similar sets of amino compounds, amides predominating. Ninety-six per cent of the fruit's nitrogen becomes incorporated into seeds. Sixteen per cent of the seed's nitrogen is mobilized from the senescing pod.The transpiration ratio of the fruit is 22.5 ml per gram dry matter accumulated. Xylem supplies 60% of a fruit's total water requirement and the equivalent of two-thirds of its transpiration loss. Phloem becomes prominent as a water donor once the seeds start to fill.The fruit exhibits a 31% conversion by weight of organic imports into food reserves of seeds. This entails an intake through vascular channels of 1756 mg sucrose and 384 mg amino compounds and an accumulation in seeds of 412 mg protein, 132 mg oil, and 110 mg perchloric acid-soluble carbohydrate.

Journal Article↗

PubMed1975

Asparagine metabolism-key to the nitrogen nutrition of developing legume seeds.

Asparagine accounted for 50 to 70% of the nitrogen carried in translocatory channels serving fruit and seed of white lupin (Lupinus albus L.). Rates of supply of the amide always greatly exceeded its incorporation as such into protein. An asparaginase (l-asparagine amido hydrolase EC 3.5.1.1) was demonstrated in crude extracts of seeds. In vitro activity was up to 5 mumoles of aspartate formed per hour per gram fresh weight at the apparent Km(Asn) value of 10 mM, and this more than accounted for the estimated rates of asparagine utilization in vivo. Asparaginase activity per seed increased 10-fold in the period 5 to 7 weeks after anthesis, coinciding with early stages of storage protein synthesis in the cotyledons.Double labeled ((14)C (U), (15)N (amide)) asparagine was fed to fruiting shoots through the transpiration steram. Fruit phloem sap analysis indicated that virtually all of the label was translocated to seeds in the form of asparagine. In young seeds (15)N from asparagine breakdown was traced to the ammonia, glutamine, and alanine of endospermic fluid, the (14)C appearing mainly in nonamino compounds. In the cotyledon-filling stage the C and N of asparagine was contributed to a variety of amino acid residues of protein.

Journal Article↗