L-dopa stimulates the release of [3H]gamma-aminobutyric acid in the basal ganglia of 6-hydroxydopamine lesioned rats

L-DOPA stimulated the K(+)-induced [3H]GABA (gamma-aminobutyric acid) release from slices of substantia nigra pars reticulata, entopeduncular nucleus, globus pallidus and caudate-putamen isolated from the ipsilateral side of 6-hydroxydopamine-lesioned rats, but the release from ipsilateral subthalamic slices was not affected. In substantia nigra, L-DOPA stimulation (EC50 = 1 microM) of [3H]GABA release was dose-dependently blocked (IC50 = 0.1 microM for the stimulation caused by 10 microM L-DOPA) by the D1 antagonist SCH 23390, but was not affected by (-)-sulpiride, a D2 antagonist. SCH 23390 also blocked the stimulation in the other nuclei. The DOPA decarboxylase inhibitor NSD-1015 (500 microM) did not prevent the stimulation induced by L-DOPA in all of the studied nuclei. The results suggest that L-DOPA is able to activate D1 receptors located on the terminals of striatal projections via the dopamine formed by a decarboxylation mediated by an NSD-1015-resistant enzyme. Activation of the presynaptic D1 receptors results in stimulation of GABA release.     

Determinants of cockroach and mouse exposure and associations with asthma in families and elderly individuals living in New York City public housing.

BACKGROUND: Asthma prevalence is high in the inner city, and morbidity has been associated with cockroach and mouse allergens. OBJECTIVE: To characterize the relationships among pests, allergens, pesticides, and asthma in New York City public housing. METHODS: In 324 apartments, dust samples collected from beds and kitchens were analyzed for cockroach (Bla g 2) and mouse (mouse urinary protein [MUP]) allergens, pest populations were monitored, and residents were interviewed about home characteristics and asthma symptoms. RESULTS: Cockroaches were found in 77% of the apartments, and evidence of mice was found in 13%. Allergens and pesticide use were associated with pest infestation, and 15% of residents reported using illegal pesticides. The percentage of apartments with high allergen levels varied significantly by building (Bla g 2: P = .002; MUP: P = .03), as did the percentage of apartments with cockroaches (P = .002) and daily mouse sightings (P = .02). Thirty-seven percent of the apartments had at least 1 resident with physician-diagnosed asthma. In family buildings, apartments with high Bla g 2 levels had 1.7 times greater odds of having an asthmatic resident (95% confidence interval, 1.2-2.3). In senior citizen buildings, apartments with high MUP levels had 6.6 times greater odds of having an asthmatic resident (95% confidence interval, 1.4-31.7), controlling for smoking and other potential confounders. CONCLUSIONS: Previous studies have identified home characteristics associated with the presence of cockroaches and mice, but the present findings suggest that building-level characteristics can affect high pest exposure. Furthermore, the high asthma prevalence in residents and the use of illegal pesticides highlight the need for safe and effective building-wide pest control strategies.     

Transition from Film to Electronic Media in the First-Year Medical School Gross Anatomy Lab

For the benefit of the first-year gross anatomy students, we digitized and published on a Web site images that had been collected over a 30-year period. We provided a CD-ROM (compact disk, read-only media) containing the image set in higher quality format to students and faculty. We supplemented basic images with hot topics such as CT angiography, virtual colonography, computer-aided diagnosis, and 3D post-processing. Full motion video and moving JPEG (Joint Photo Expert Group) animations were integrated into the atlas. On the post course questionnaire medical students reported that the images on CD-ROM were helpful during the course and for review prior to examinations. Faculty and medical students used the CD-ROM for problem-based learning sections and facilitator training. The images were clear and easily projected during review sessions and were useful for the small group sessions, where they served as examples of normal anatomy.     

In vitro studies on the mechanism of action of a new antiallergic,Ro 21-7634

The effects of Ro 21-7634 and disodium cromoglycate (cromoglycate) on the in vitro release of mediators of anaphylaxis from rat peritoneal cells and guinea pig lung tissue were compared. Ro 21-7634 was 25 fold more potent than cromoglycate as an inhibitor of antigen-induced histamine release from passively sensitized (IgE) rat peritoneal cells. Ro 21-7634 was also the more potent inhibitor of both compound 48/80- and concanavalin A-induced histamine release from rat peritoneal cells. The two drugs shared the common properties of producing the same maximal level of inhibition in each of the above releasing systems and exhibiting a time and concentration dependent loss of inhibitory activity when added to the cells prior to the releasing agent. Neither drug inhibited ionophore A23187- or ionophore X537A-induced histamine release from these cells. Ro 21-7634 inhibited antigen-induced (IgG₁) histamine and SRS-A release from actively sensitized guinea pig lung fragments, whereas cromoglycate did not. The results indicate that Ro 21-7634 and cromoglycate act through a common mechanism to inhibit allergic mediator release and that Ro 21-7634 is the more potent inhibitor.     

Adaptation to audiotactile asynchrony

Previous research has revealed the existence of perceptual mechanisms that compensate for slight temporal asynchronies between auditory and visual signals. We investigated whether temporal recalibration would also occur between auditory and tactile stimuli. Participants were exposed to streams of brief auditory and tactile stimuli presented in synchrony, or else with the auditory stimulus leading by 75 ms. After the exposure phase, the participants made temporal order judgments regarding pairs of auditory and tactile events occurring at varying stimulus onset asynchronies. The results showed that the minimal interval necessary to correctly resolve audiotactile temporal order was larger after exposure to the desynchronized streams than after exposure to the synchronous streams. This suggests the existence of a mechanism to compensate for audiotactile asynchronies that results in a widening of the temporal window for multisensory integration.     

Assessing the effect of visual and tactile distractors on the perception of auditory apparent motion

In this study we investigated the effect of the directional congruency of tactile, visual, or bimodal visuotactile apparent motion distractors on the perception of auditory apparent motion. Participants had to judge the direction in which an auditory apparent motion stream moved (left-to-right or right-to-left) while trying to ignore one of a range of distractor stimuli, including unimodal tactile or visual, bimodal visuotactile, and crossmodal (i.e., composed of one visual and one tactile stimulus) distractors. Significant crossmodal dynamic capture effects (i.e., better performance when the target and distractor stimuli moved in the same direction rather than in opposite directions) were demonstrated in all conditions. Bimodal distractors elicited more crossmodal dynamic capture than unimodal distractors, thus providing the first empirical demonstration of the effect of information presented simultaneously in two irrelevant sensory modalities on the perception of motion in a third (target) sensory modality. The results of a second experiment demonstrated that the capture effect reported in the crossmodal distractor condition was most probably attributable to the combined effect of the individual static distractors (i.e., to ventriloquism) rather than to any emergent property of crossmodal apparent motion.     

Efficacy and safety of mometasone furoate nasal spray in nasal polyposis

BACKGROUND: Studies have suggested that topical corticosteroids are effective in the treatment of nasal polyps; however, this has yet to be confirmed in a large, robust clinical trial. OBJECTIVE: To evaluate the efficacy and safety of mometasone furoate nasal spray (MFNS) for nasal polyposis. METHODS: A total of 354 subjects with bilateral nasal polyps and clinically significant congestion/obstruction participated in this multinational, randomized, double-blind, placebo-controlled study. Subjects received MFNS 200 microg once or twice daily or placebo for 4 months. Coprimary endpoints were (1) change from baseline to last assessment in physician-evaluated bilateral polyp grade score and (2) change from baseline averaged over month 1 in subject-assessed nasal congestion/obstruction. ANOVA was used for all efficacy endpoints, except for change in bilateral polyp grade score, for which baseline polyp grade was added as a covariate. RESULTS: Compared with placebo, MFNS 200 microg administered once or twice daily produced significantly greater reductions in bilateral polyp grade score (P < .001, P = .010, respectively) and congestion/obstruction (P = .001, P < .001), as well as improvement in loss of smell (P < .001, P = .036), anterior rhinorrhea (P < .001 for both), and postnasal drip (P < .001, P = .001) over month 1. MFNS 200 microg twice daily was superior to MFNS 200 microg once daily in reducing congestion/obstruction (P = .039), and there were more improvers in the MFNS 200 microg twice daily group (P = .035). MFNS was well tolerated in both groups. CONCLUSION: MFNS 200 mug, once or twice daily, was safe and significantly superior to placebo in reducing polyp grade (size and extent) and improving congestion/obstruction and return of sense of smell. MFNS is an effective medical treatment for nasal polyposis and may reduce or delay the need for surgery.     

Ventromedial hypothalamus vs. lateral hypothalamic D2 satiety receptors in the body weight increase induced by systemic sulpiride

Two experiments were conducted in order to see if dopamine satiety receptors in the lateral hypothalamus or satiety mechanisms in the ventromedial hypothalamus were involved in the hyperphagia and body weight increase induced by systemic sulpiride. In the first experiment, it was shown that systemic sulpiride (20 mg/kg) does not block the anorexia caused by intraperifornical injections of amphetamine. In the second experiment, sulpiride (20 mg/kg during 18 days) did not produce an additional increase in body weight in previously VMH-lesioned female rats. This last fact cannot be explained by a ceiling effect since insulin (5 U/day during 7 days) increased body weight in the same VMH rats in which sulpiride was not effective. These results do not support the hypothesis that systemic sulpiride reaches the perifornical dopamine D2 receptors to disinhibit feeding, but suggest instead an involvement of the ventromedial hypothalamus. This last suggestion is more in agreement with the hypothesis that sulpiride alters feeding and body weight gain through the induction of a functional gonadectomy.