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S Travers

Publications and source records attributed to S Travers.

10 recordsLinked to original sources
PubMed2001

The effects of attention on perceptual implicit memory.

Reports on the effects of dividing attention at study on subsequent perceptual priming suggest that perceptual priming is generally unaffected by attentional manipulations as long as word identity is processed. We tested this hypothesis in three experiments by using the implicit word fragment completion and word stem completion tasks. Division of attention was instantiated with the Stroop task in order to ensure the processing of word identity even when the participant's attention was directed to a stimulus attribute other than the word itself. Under these conditions, we found that even though perceptual priming was significant, it was significantly reduced in magnitude. A stem cued recall test in Experiment 2 confirmed a more deleterious effect of divided attention on explicit memory. Taken together, our findings delineate the relative contributions of perceptual analysis and attentional processes in mediating perceptual priming on two ubiquitously used tasks of word fragment completion and word stem completion.

Adult↗
PubMed2001

E-commerce in healthcare: changing the traditional landscape.

The healthcare industry, with more than one trillion dollars in revenue, accounts for about one-seventh of the U.S. economy. A significant portion of this revenue is lost to escalating healthcare system costs. This article examines the shortcomings of the traditional healthcare delivery system in terms of information flow, communication standards, case collections, and IT spending. It makes the case that e-commerce has the ability to transact some healthcare business more efficiently and cost-effectively. With the Internet as a delivery platform, several models offer improvement over the status quo.

Commerce↗
PubMed2000

Detection and prevalence of early diabetic retinopathy in juvenile diabetics with diabetes for 10 years or more.

PURPOSE: To compare clinical examination using green light with clinical examination using white light in detecting early diabetic retinopathy (DR) in juvenile diabetic patients with disease for 10 or more years. METHODS: All patients were examined clinically using both green light and white light to determine the presence of DR. Each patient underwent seven-field fundus photography, which was used as the defined standard against which the clinical examinations were compared and also to determine the prevalence of DR. Data on age at diagnosis, duration of diabetes mellitus, recent HbA1c levels, treatment for systemic hypertension and microalbuminuria were obtained from medical records. RESULTS: When compared with the defined standard, fundal examination with green light was more sensitive, more specific and had higher predictive values than examination with white light in the detection of early DR. The overall prevalence of DR was 44%, which in all cases was classified as minimal to mild background DR. Patients with DR had significantly higher mean HbA1c levels than those without (p = 0.016). There was no significant association between the prevalence of DR and age at time of examination or diagnosis, duration of diabetes, patient gender, microalbuminuria levels or treatment for systemic hypertension. CONCLUSION: Fundal examination with green light is better than white light in detecting early DR in juvenile diabetics with duration of disease of 10 years or more. Furthermore the presence of DR is associated with poorer diabetic control. Due to coincident lifestyle changes and the probability of long duration of disease, accurate detection of early DR in juvenile diabetics with diabetes for over 10 years is important.

Adolescent↗
PubMed1999

Onset and duration of action of levocabastine nasal spray in atopic patients under nasal challenge conditions.

BACKGROUND: Although prior studies have documented the rapid onset of action of topical intranasal levocabastine (LEV), little is known about its duration of action under nasal challenge conditions. OBJECTIVES: We sought to assess the onset and duration of action of escalating doses of LEV nasal spray by using a nasal allergen challenge (NAC) model. METHODS: Eighteen asymptomatic subjects with histories of seasonal allergic rhinitis were enrolled into a randomized, single-blind, placebo-controlled, dose-ranging crossover study. Each patient was randomly assigned to receive single doses of placebo and intranasal LEV 0.1, 0.2, and 0.4 mg during 2 parts of the study. In part 1 (onset of action), NAC consisted of a single dose of allergen administered 5 minutes after study drug treatment. In part 2 (duration of action), NAC consisted of increasing doses of allergen administered 0.5, 6, 12, and 24 hours on separate days after study drug treatment. Nasal symptom scores (NSSs) and nasal peak expiratory flow rates were measured after NAC in both phases of the study. Blood samples for plasma LEV concentrations were drawn after each NAC. RESULTS: In part 1, NSSs were significantly lower after the administration of LEV 0.1, 0.2, and 0.4 mg compared with placebo (P <.05). In part 2, NSSs were significantly lower after LEV doses of 0.2 and 0.4 mg compared with placebo at 0.5, 6, 12, and 24 hours after treatment (P <.05). The mean provocative dose of allergen required to elicit a positive nasal reaction was increased after LEV doses of 0.2 and 0.4 mg at 0.5, 6, and 12 hours after treatment. Nasal peak expiratory flow rates demonstrated no significant differences between LEV and placebo for any doses at any time points. Mean plasma LEV concentrations were low (range, 0 to 3. 7 ng/mL) after all doses and did not correlate with drug efficacy. CONCLUSIONS: Single intranasal LEV doses of 0.1, 0.2, and 0.4 mg significantly reduced the severity of the immediate nasal response to allergen when administered 5 minutes before NAC. This protective effect against NAC continued to be present 24 hours after administration of LEV doses of 0.2 and 0.4 mg. Efficacy in blocking the reaction to NAC did not correlate with plasma LEV levels, suggesting that the inhibitory effect was due largely to topical rather than systemic effects.

Administration, Intranasal↗
PubMed1999

Lack of effect of erythromycin and ketoconazole on the pharmacokinetics and pharmacodynamics of steady-state intranasal levocabastine.

The single-dose effects of the cytochrome P-450 inhibitors erythromycin and ketoconazole on the steady-state pharmacokinetics and electrocardiographic repolarization pharmacodynamics of intranasal levocabastine, a potent and selective H1-receptor antagonist, were evaluated in healthy young male subjects. Two randomized, open-label, placebo-controlled, two-way crossover studies were performed. Levocabastine nasal spray was administered as two sprays per nostril (0.05 mg/spray) twice daily (for a total daily dose of 0.4 mg) for 6 days. On Day 7, a single dose of 0.2 mg was administered followed immediately by a single dose of either oral placebo, erythromycin 333 mg, or ketoconazole 200 mg. In all treatment groups, levocabastine was rapidly absorbed, with peak plasma concentrations reached at approximately 3 hours in the erythromycin study and 2.8 hours in the ketoconazole study. The mean terminal half-life was approximately 45 and 44 hours, respectively. In both studies, mean steady-state plasma concentrations and pharmacokinetics of levocabastine following the single doses of erythromycin or ketoconazole were not significantly different from corresponding values seen with the concomitant administration of the placebo. No clinically significant mean changes from baseline in QT or QTc (QT corrected for heart rate) intervals occurred in any of the treatment groups, and none of the subjects in either study experienced abnormally prolonged QTc intervals. Intranasal levocabastine was well tolerated, with no difference in the incidence of adverse events between treatment groups in either study; adverse events were generally mild in severity. Since levocabastine undergoes only minimal hepatic metabolism and is not a substrate for or an inhibitor of cytochrome P-450, the likelihood of systemic drug interactions with drugs affecting the cytochrome P-450 system is minimal.

Administration, Intranasal↗
PubMed1999

Advances in the recognition and treatment of endocrine complications in children with chronic illness.

Children with chronic illness live with the specific consequences of their illness, as well as secondary endocrine abnormalities that further compromise growth and pubertal development. These secondary abnormalities may significantly add to their physiologic and psychological burden. Although these endocrine abnormalities theoretically arise as adaptations to the chronic illness, they may have deleterious effects if they persist untreated. Children with HIV infection and other wasting disorders, for example, show growth suppression out of proportion to the severity of their primary illness as a result of growth hormone resistance and enhanced cortisol secretion. In hematologic conditions such as sickle cell anemia, thalassemia, or bone marrow transplant, damage to the hypothalamus and/or pituitary may lead to growth hormone deficiency, gonadal insufficiency, and hypothyroidism. Growth and pubertal delay are also common among children with cystic fibrosis, along with insulin-dependent diabetes mellitus caused by pancreatic fibrosis. Similarly, children receiving long-term steroid therapy have delays in growth and pubertal development, accompanied by risk for osteoporosis, whereas chronic renal disease is associated with growth and pubertal delay, as well as secondary hyperparathyroidism. Recognition of potential endocrinopathies in children with chronic illness is an important aspect of the care of these children because the disturbances are frequently amenable to treatment, permitting full or partial restoration of normal growth and development in these children. In this chapter, the endocrine consequences of common chronic conditions of childhood are reviewed, as well as the etiology of the endocrine disturbance, the clinical consequences, and recommendations for treatment.

Adolescent↗
PubMedDate not supplied

Efficacy and safety of levocabastine nasal spray for seasonal allergic rhinitis.

This multicenter, double-blind, placebo-controlled trial evaluated the efficacy and safety of levocabastine nasal spray, a potent and selective H1-receptor antagonist, in the control of histamine-mediated symptoms of seasonal allergic rhinitis. Adults with > or = 2 year history of allergic rhinitis due to Mountain Cedar were randomized to treatment with levocabastine nasal spray (0.2 mg twice daily) or placebo for 28 days during the 1994-1995 Mountain Cedar allergy season. Patients assessed the severity of their rhinitis symptoms on a four-point scale twice daily. At the end of the trial, patients also performed a global evaluation of treatment efficacy on a five-point scale. Overall for the 4-week treatment period, levocabastine nasal spray significantly reduced major nasal (runny nose and sneezing) and primary rhinitis (runny nose, sneezing, and itchy/gritty eyes) symptoms compared with placebo on both repeated measures (p = 0.023; p = 0.01) and ANOVA (p = 0.003; p < 0.001) analyses. Global evaluations of treatment efficacy at the end of the trial significantly favored levocabastine over placebo (p = 0.002). Overall, the incidence of adverse events was similar for both treatment groups. In general, most adverse events were mild in intensity, with sinusitis (17% each group), headache (17% placebo, 14% levocabastine), and rhinitis (8% placebo, 2% levocabastine) most commonly reported. Levocabastine nasal spray 0.2 mg twice daily was significantly more effective than placebo in the relief of histamine-mediated symptoms in patients with seasonal allergic rhinitis and was well tolerated over the 28-day treatment period.

Administration, Intranasal↗