Quantum dynamics with Bohmian trajectories.

We describe the advantages and disadvantages of numerical methods when Bohmian trajectory grids are used for numerical simulations of quantum dynamics. We focus on the crucial noncrossing property of Bohmian trajectories, which, numerically, must be given careful attention. Failure to do so causes instabilities or leads to false simulations.

[17 year old patient with acute abdominal pain, hematochezia and exanthema]. / 17-jähriger Mann mit akuten Bauchschmerzen, Hämatochezie und Exanthem.

A 17-year old adolescent presented with abdominal pain, petechial lesions, arthralgia, and hematochezia. Abdominal ultrasound showed a suspicious ileocecal region and a lower endoscopy revealed the picture of an ileitis terminalis. The diagnosis of Purpura Henoch Schoenlein was made and confirmed by skin-biopsy showing a leucocytoclastic vasculitis. This case report demonstrates the various clinical symptoms of Purpura Henoch Schoenlein and its clinical course.

Synthesis and structure-activity relationships of benzophenone hydrazone derivatives with insecticidal activity.

A broad range of benzophenone hydrazone derivatives was prepared and tested against selected chewing insect pests, allowing the analysis of structure-activity relationships. Good activity was found only when the aromatic rings were substituted at the 4-positions with an halogen atom and a triflate or perhaloalkoxy group. In contrast, a number of substituents on the hydrazone part led to active compounds, the best results being achieved with acyl-type substituents. The excellent laboratory and greenhouse activity of the best representatives was confirmed in semi-field trials against Spodoptera littoralis.

Impact of rhinosinusitis in health care delivery: the Quebec experience.

OBJECTIVE: Rhinosinusitis is a common disease affecting 135 per 1,000 population. The cost and the impact on quality of life of this disease are considerable. Health care delivery for a particular disease is evaluated through the health impact of the disease, outcomes of treatments, and their costs. This article reviews our experience with rhinosinusitis and its impact on health, as measured using a generic quality of life instrument, the Medical Outcome Study 36-Item Short-Form Health Survey (SF-36), in a selected patient population. Outcomes of treatments will be introduced, and the economic impact of chronic rhinosinusitis based on a U.S. study will be discussed. MATERIAL AND METHODS: One hundred and ten patients (divided into three subgroups: recurrent acute rhinosinusitis, chronic rhinosinusitis, and nasal polyposis) completed the SF-36 survey on the day of the diagnostic visit in the outpatient sinus clinics of two hospitals. RESULTS: The scores of the SF-36, in chronic rhinosinusitis, are compared with the normative values of a healthy U.S. population showing statistically significant differences in seven of eight domains. A comparison of the scores of chronic rhinosinusitis with a U.S. study on chronic rhinosinusitis shows statistically significant differences in five of eight domains. A comparison of the scores in the three diagnostic subgroups shows a statistical significance in two domains: bodily pain and vitality are more affected in recurrent acute and chronic rhinosinusitis. CONCLUSIONS: Chronic rhinosinusitis affects the quality of life of patients with rhinosinusitis and represents an important health burden. Some differences are noted with the U.S. chronic rhinosinusitis population. Recurrent acute and chronic rhinosinusitis seem to have more impact on vitality and bodily pain than nasal polyposis.

St John's Wort induces intestinal P-glycoprotein/MDR1 and intestinal and hepatic CYP3A4.

BACKGROUND: St John's Wort (hypericum perforatum) is an herbal medicine that is frequently used for therapy of mild depression. Recently, St John's Wort was reported to substantially decrease blood/plasma concentrations and efficacy of cyclosporine (INN, ciclosporin), indinavir, and digoxin. In this study we investigated the mechanisms of these St John's Wort-induced drug interactions. METHODS AND RESULTS: In a preclinical study, the administration of St John's Wort extract to rats during 14 days resulted in a 3.8-fold increase of intestinal P-glycoprotein/Mdrl expression and in a 2.5-fold increase in hepatic CYP3A2 expression (Western blot analyses). In a clinical study, the administration of St John's Wort extract to 8 healthy male volunteers during 14 days resulted in an 18% decrease of digoxin exposure after a single digoxin dose (0.5 mg), in 1.4- and 1.5-fold increased expressions of duodenal P-glycoprotein/MDR1 and CYP3A4, respectively, and in a 1.4-fold increase in the functional activity of hepatic CYP3A4 (14C-erythromycin breath test). CONCLUSIONS: These results indicate direct inducing effects of St John's Wort on intestinal P-glycoprotein/MDR1 (in rats and humans), hepatic CYP3A2 (in rats), and intestinal and hepatic CYP3A4 (in humans). Therefore the results provide a mechanistic explanation for the previously observed drug interactions in patients and support the importance of intestinal P-glycoprotein/MDR1 in addition to intestinal and hepatic CYP3A4 for overall drug absorption and disposition in humans.

Influence of environmental enrichment and sex on predator stress response in rats.

Based on sex, rats were randomly assigned to either an enriched or standard environment for 30 days prior to behavioral testing. The predator stress testing consisted of placing the rat in a cat avoidance apparatus so that the rat's behavioral response to a natural stressor, the cat, could be assessed. The rats were subsequently exposed to a partial predator stimulus (cat urine) that was placed in the home cages for 7 days. Each animal was then sacrificed and the stomach, adrenal glands, and thymus gland were removed and assessed. Results indicated that 1) the enriched rats engaged in less defensive behavior than the standard rats during behavioral testing, 2) female rats demonstrated more defensive behavioral patterns compared to male rats, and 3) the enriched environment affected females more than males, as evidenced by the interaction effects on various recorded behaviors.

Practical clinical applications of sports dentistry in private practice.

Preparing a practice to become "trauma-ready" involves more than educating the dentist and the staff in the proper management of dentofacial trauma. All members of the office should understand their roles in preventing and treating trauma. They must be willing to provide care after hours when called upon to do so. Dentists who want to be more involved might wish to volunteer their services as sports dentists for local school or recreational league teams. The dentist who is conscious of his or her patients who are at risk for sports-related trauma will also find others in the practice who might benefit from many of the same protective devices that are being constructed for athletes. These include children involved in higher-risk activities, developmentally disabled patients, patients undergoing general anesthesia, and others. Being trauma-ready may open up several rewarding activities for the practice because of the many spin-off applications. The trauma-ready practice must also be cognizant of the some-times perplexing legal and insurance issues with regard to preventing and treating sport-related injuries. In addition to lowering the risk exposure to the practice, the dentist can help ensure the maximum third-party benefits for the patient.

Fluoride uptake into demineralized primary enamel from fluoride-impregnated dental floss in vitro.

Fluoridated mouthrinses are not advised for preschool children who may swallow much of the agent. An alternate method of delivering topical fluoride to the interproximal tooth surfaces in these young patients may be fluoridated dental floss. The purpose of this study was to determine the fluoride levels of demineralized primary enamel both before and after the use of a commercially available dental floss impregnated with commercially available fluoride-containing products. The results showed that demineralized primary tooth surfaces treated with fluoride-impregnated dental floss exhibited significantly higher fluoride levels than those surfaces treated by immersion in a fluoridated mouthrinse or deionized water.

Otologic manifestations in congenital velopharyngeal insufficiency.

A study of ear disease in children with congenital velopharyngeal insufficiency (VPI) was undertaken. A retrospective chart analysis of 80 cases of VPI formed the basis of this review. Thirty-seven percent of the children had evidence of middle ear disease, with middle ear effusion and recurrent otitis media being the most frequent findings. Thirty-one percent had abnormal audiograms, with 20% having a conductive or mixed hearing loss. Overall, 46% of the children had otologic manifestations, indicating the need for the pediatrician and the otolaryngologist together to be actively involved in the evaluation and treatment of this group of children, starting in early infancy.

Monitoring of sedated pediatric dental patients.

The results of this study showed that children sedated with 50 mg/kg chloral hydrate and 25 mg hydroxyzine in conjunction with 40 percent nitrous oxide and 60 percent oxygen may have respiratory difficulties which are not detected by the traditional monitoring of blood pressure, pulse, respiratory rate and skin color. The use of a pulse oximeter that noninvasively measures oxygen saturation of hemoglobin (SaO2) allowed earlier detection of respiratory distress, when correction was a relatively simple matter of readjusting head position. This combination of sedative agents was effective in managing two-thirds of the patients originally classified in a behavioral category of definitely negative. No children sedated with only 40 percent nitrous oxide and 60 percent oxygen exhibited respiratory problems, and over 80 percent of the patients classified in behavioral category of negative were managed effectively with this technique.

Dimensional stability of alginate impressions immersed in disinfecting solutions.

The stability of full-arch alginate impressions that had been immersed in one of two disinfecting solutions was assessed by measuring stone casts poured from the alginate impressions. Statistically significant dimensional changes occurred, when compared with master casts, but only by 1 mm or less, a clinically insignificant amount.