Differential ability of D1 and D2 dopamine receptor agonists to induce and modulate expression and reinstatement of cocaine place preference in rats

Rationale D1-Like agonists are self-administered by drug-naive animals, whereas D2-like agonists reinstate cocaine-seeking behavior, but the rewarding and reinstating effects of D1- and D2-like agonists in pavlovian-based conditioned place preference are equivocal. Objective To compare the ability of D1 and D2 agonists to produce conditioned place preference with their modulation of expression and reinstatement of an established cocaine place preference. Methods Using an unbiased procedure, we measured the place preference induced by the D1 receptor agonist SKF 81297 and the D2/D3 receptor agonist quinpirole in drug-naive or cocaine-exposed rats. The rewarding effects of the D1 agonists SKF 82958, ABT-431, A-77636, and the D2/D3 receptor agonist 7-OH-DPAT were also tested. Additionally, we tested the ability of SKF 81297 and quinpirole to modulate expression and reinstatement of an established cocaine place preference. Results The D1 receptor agonists SKF 81297, SKF 82958, and ABT-431 produced dose-dependent conditioned place preferences, whereas A-77636 produced only place aversion, and the D2/D3 agonists quinpirole and 7-OH-DPAT were without effect in drug naive rats. In cocaine-treated rats, SKF-81297-induced place preference was reduced, whereas quinpirole-induced place preference was revealed. Pretreatment using either D1 or D2/D3 agonists blocked expression of an established cocaine place preference, but only the D1 agonist SKF 81297 and cocaine dose-dependently reinstated an extinguished cocaine place preference, whereas the D2/D3 agonist quinpirole induced place aversion but failed to alter cocaine-induced reinstatement. Conclusions D1, but not D2/D3, agonists mediate rewarding effects and reinstatement of cocaine place preference, but the reinstating effects differ markedly from self-administration paradigms.     

Preoperative angiography of the iliofemoral vessels in hip revision surgery of massive acetabular bone defects

Hip arthroplasty, and particularly revision surgery, may be complicated by injury to the large vessels on rare occasions, and this can be responsible for severe sequelae. The potential for vascular damage is increased when acetabular osteolysis is followed by medial dislocation of the socket. We report preliminary experience in performing preoperative arteriography of the iliofemoral vessels in 15 patients affected with endopelvic protrusion of the acetabular component. Digital angiography was helpful in defining the precise relationship between the arteries and the prosthesis. When the cup revealed a close proximity to the major vascular structures (10 cases), revision hip surgery was preceded by a laparotomic approach to isolating pelvic vessels, thus permitting an immediate control of the potentially massive bleeding. Received: 3 June 2000/Accepted: 26 June 2000     

The survival of adenovirus in multidose bottles of topical fluorescein

PURPOSE: To determine if common ocular adenovirus serotypes survive in vitro in multidose bottles of topical fluorescein (Fluress; Pilkington Barnes Hind, Inc, Sunnyvale, California).METHODS: Clinical isolates of adenovirus types 8 and 19 were inoculated separately into 10 bottles each of Fluress and maintained at room temperature (25 C). All bottles were titered for adenovirus on A549 cell monolayers at 0, 7, 14, 21, 28, and 49 days.RESULTS: Adenovirus was recovered from Fluress for up to 21 days for adenovirus type 19 and 28 days for adenovirus type 8.CONCLUSION: A multidose bottle of Fluress contaminated with adenovirus can be a potential source of adenoviral transmission in an ophthalmic office setting.     

Chikungunya virus, Cameroon, 2006

We report the isolation of chikungunya virus from a patient during an outbreak of a denguelike syndrome in Cameroon in 2006. The virus was phylogenetically grouped in the Democratic Republic of the Congo cluster, indicating a continuous circulation of a genetically similar chikungunya virus population during 6 years in Central Africa.     

Relationship between ankle frontal muscle powers and three-d gait patterns

OBJECTIVE: This study was undertaken to demonstrate that the ankle frontal muscle power absorption and generation at push-off are related to the foot's initial position at heel-strike with respect to the body center of mass. DESIGN: Nineteen able-bodied male subjects participated in this study and were divided into two groups according to ankle frontal plane power generation or absorption at push-off. RESULTS: At heel-strike, the group that absorbed had a center of pressure that was located on average 25% more anteriorly and 36% more laterally to the body center of mass. Moreover, at push-off, the center of pressure was closer (26%) to the center of mass than in the generating group. The absorbing group compensated by increasing their sagittal plane hip energy by 30% to pull the lower limb forward and their knee power absorption by 47% to slow down the leg before the subsequent heel-strike. CONCLUSIONS: The foot's initial position at heel-strike explains in part the ankle frontal power generation or absorption at push-off. Increasing hip and knee sagittal joint powers and mechanical energies were the main contributors in compensating and providing a broader base of support and frontal plane ankle power absorption.