Pulsations with reflected boundary waves: a hydrodynamic reverse transport mechanism for perivascular drainage in the brain.

Beta-amyloid accumulation within arterial walls in cerebral amyloid angiopathy is associated with the onset of Alzheimer's disease. However, the mechanism of beta-amyloid clearance along peri-arterial pathways in the brain is not well understood. In this study, we investigate a transport mechanism in the arterial basement membrane consisting of forward-propagating waves and their reflections. The arterial basement membrane is modeled as a periodically deforming annulus filled with an incompressible single-phase Newtonian fluid. A reverse flow, which has been suggested in literature as a beta-amyloid clearance pathway, can be induced by the motion of reflected boundary waves along the annular walls. The wave amplitude and the volume of the annular region govern the flow magnitude and may have important implications for an aging brain. Magnitudes of transport obtained from control volume analysis and numerical solutions of the Navier-Stokes equations are presented.

A collaborative study of a new antidepressant, viloxazine, in neurotic and endogenous depressives.

In a multicenter series of trials, viloxazine was compared with imipramine, amitriptyline, doxepin and placebo in 123 neurotic and endogenous depressive inpatients and outpatients. While significant period effects reflecting improvement were obtained on the majority of efficacy variables, no significant differences were obtained among the treatment groups or depressive types. Imipramine and amitriptyline exhibited more anticholinergic adverse reactions; while, viloxazine exhibited greater CNS effects. Dizziness and nausea were much more frequent in neurotic depressives which may be related to their psychopathology.

Viloxazine in the treatment of depressive neurosis: a controlled clinical study with doxepin and placebo.

In a four-week, double-blind, clinical trial thirty-one patients with depressive neurosis were treated with viloxazine, doxepin, or placebo. There were no differences among the three groups in therapeutic effects. Many depressed out-patients improve on placebo. Viloxazine hydrochloride is one of a series of compounds developed to explore the central nervous system activity of the aryloxypropanolamine type of beta-adreno-receptor antagonists. Initial clinical study support the hypothesis that viloxazine has antidepressant properties in man (Bayliss et al, 1974; Bereen, 1973; Pichot et al., 1975; Tsegos and Ekdawi, 1974).

Mianserin: determination of therapeutic dose range.

Mianserin hydrochloride is a tetracyclic antidepressant with an EEG and clinical activity profile similar to amitriptyline. To investigate the drug's optimal dosage range, a 6-week open comparative trial sequentially assigned 12 depressed patients to one of three dose ranges (60, 90 and 120 mg). Improvement occurred in depressive symptomatology in all three treatment groups. There was no differential improvement noted in any group; however, the incidence of adverse effects was greater in the middle (90 mg) and high (120 mg) dose ranges.