Pablo Henny and Barbara E. Jones Department of Neurology and Neurosurgery, McGill University, Montreal Neurological Institute, Montreal, Quebec, Canada H3A 2B4

Abstract: The present study was undertaken to characterize the pre- and postsynaptic constituents of the basal forebrain (BF) projection to the prefrontal cortex in the rat, and determine whether it includes glutamatergic in addition to established ?-aminobutyric acid (GABA)ergic and cholinergic elements. BF fibres were labelled by anterograde transport using biotin dextran amine (BDA) and dual-stained for the vesicular transporter proteins (VTPs) for glutamate (VGluT), GABA (VGAT) or acetylcholine (VAChT). Viewed by fluorescence microscopy and estimated by stereology, proportions of BDA-labelled varicosities were found to be stained for VGluT2 (and not VGluT1 or 3), VGAT or VAChT (representing, respectively, ~15%, ~52% and ~19% within the infralimbic cortex). Each type was present in all, though commonly most densely in deep, cortical layers. Material was triple-stained for postsynaptic proteins to examine whether BDA+VTP+ varicosities might form excitatory or inhibitory synapses, respectively, labelled by postsynaptic density-95 kDA (PSD-95) or gephyrin (Geph). Viewed by confocal microscopy, a majority of BDA+/VGluT2+ varicosities were found to be apposed to PSD-95+ elements, and a majority of BDA+/VGAT+ varicosities to be apposed to Geph+ elements. Other series were triple-stained for cell marker proteins to assess whether the varicosities contacted interneurons or pyramidal cells. Viewed by confocal microscopy, BDA-labelled VGluT2+, VGAT+ and VAChT+ BF terminals were all found in contact with calbindin+ interneurons, whereas VGAT+ BF terminals were also seen in contact with parvalbumin+ interneurons and non-phosphorylated neurofilament+ pyramidal cells. Through distinct glutamatergic, GABAergic and cholinergic projections, the BF can thus influence cortical activity in a diverse manner.

BARBOSA-FILHO, José M., CUNHA, Renildo M., DIAS, Celidarque S. et al. "GC-MS analysis and cardiovascular activity of the essential oil of Ocotea duckei. Rev. bras. farmacogn., Jan./Mar. 2008, vol.18, no.1, p.37-41. ISSN 0102-695X.

Abstract: The essential oils obtained by steam distillation from the roots, stems, leaves and fruits of Ocotea duckei had their composition analyzed by GC-MS. The pharmacological activity of these oils was also evaluated showing significant cardiovascular effects. Forty-nine substances were identified, consisting of a complex mixture of monoterpenes (45%) and sesquiterpenes (55%). The fruits yielded (1.9%) more essential oil than the stems (1.0%), roots (0.8%) and leaves (0.7%). The main component in the oil of the leaves was trans-caryophyllene (60.54%), in the stem bark b-eudesmol (27.51%) and in the fruits, dl-limonene (30.12%). The predominant essential oil component in the roots was elemol (24.31%). In non-anaesthetized normotensive rats, the essential oils from different parts of Ocotea duckei (leaves, fruits, stem and roots) induced significant (p < 0.05) hypotension followed by bradycardia.

Klaus Ehrmann PhD, Arthur Ho MOptom PhD FAAO, Jean-Marie Parel Ing ETS-G PhD (2008) "Biomechanical analysis of the accommodative apparatus in primates." Clinical and Experimental Optometry 91 (3) , 302–312 doi:10.1111/j.1444-0938.2008.00247.x

Background: The restoration of natural accommodation in the presbyopic and cataract affected eye is a subject of intense research effort. A new instrument has been developed to test the viability and efficacy of procedures and methods to restore accommodation ex vivo in animal or human eyes.

Methods: A section of the globe containing the crystalline lens, zonules, ciliary muscle and sclera is bonded into eight curved shoes. After dissecting the sclera between the shoes, even radial load is applied to stretch the zonules and capsular bag to simulate the natural accommodative process. The associated change in optical power is measured using a modified Scheiner's disk method. Changes in the diameter of the lens and ciliary processes are recorded, as well as zonular load.

Results: No effective change in power was observed for the three presbyopic human eyes under four millimetres diameter stretching; the diameter of the ciliary aperture increased by between 1.8 mm and 2.3 mm, while the maximum increase in lens diameter was 0.19 mm. For the three younger monkey eyes, the diameter of the ciliary aperture increased by 1.4 mm with a corresponding increase in the lens diameter of between 0.50 mm and 0.65 mm. Stretching forces were generally higher for the human than for the monkey eyes, reaching maxima of 35 mN and 52 mN, respectively. The monkey eyes changed power by between 9.1 and 10.1 dioptres. An almost identical, progressive increase for lens diameter, power and stretching force versus stretch distance was found for all three monkey eyes.

Conclusion: The better understanding of the mechanisms and forces involved in the primate accommodative apparatus will assist with the development of accommodating IOLs and other methods to restore accommodation.