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Abstract: We examined the effects of the endocannabinoide-anandamide (AEA), the synthetic cannabinoid, WIN55,212-2, and the active phorbol ester, 4-β-phorbol 12-myristate 13-acetate (4-β-PMA), on the release of [3H]d-Aspartate ([3H]d-ASP) from rat hippocampal synaptosomes. Release was evoked with three different stimuli: (1) KCl-induced membrane depolarization, which activates voltage-dependent Ca2+ channels and causes limited neurotransmitter exocytosis, presumably from ready-releasable vesicles docked in the active zone; (2) exposure to the Ca2+ ionophore-A23187, which causes more extensive transmitter release, presumably from intracellular reserve vesicles; and (3) K+ channel blockade by 4-aminopyridine (4-AP), which generates repetitive depolarization that stimulates release from both ready-releasable and reserve vesicles. AEA produced concentration-dependent inhibition of [3H]d-ASP release stimulated with 15mM KCl (E max =47.4±2.8; EC50 =0.8μM) but potentiated the release induced by 4-AP (1mM) (+22.0±1.3% at 1μM) and by A23187 (1μM) (+98.0±5.9% at 1μM). AEA''s enhancement of the [3H]d-ASP release induced by the Ca2+ ionophore was mimicked by 4-β-PMA, which is known to activate protein kinase C (PKC), and the increases produced by both compounds were completely reversed by synaptosome treatment with staurosporine (1μM), a potent PKC blocker. In contrast, WIN55,212-2 inhibited the release of [3H]d-ASP evoked by KCl (E max =47.1±2.8; EC50 =0.9μM) and that produced by 4-AP (−26.0±1.5% at 1μM) and had no significant effect of the release induced by Ca2+ ionophore treatment. AEA thus appears to exert a dual effect on hippocampal glutamatergic nerve terminals. It inhibits release from ready-releasable vesicles and potentiates the release observed during high-frequency stimulation, which also involves the reserve vesicles. The latter effect is mediated by PKC. These findings reveal novel effects of AEA on glutamatergic nerve terminals and demonstrate that the effects of endogenous and synthetic cannabinoids are not always identical. [Copyright &y& Elsevier]

Purpose Gambling disorder has been recently reclassified under the category "substance-related and addictive disorders". Recent studies performed through functional MRI (fMRI) have shown that the perseverance of some behaviors can alter brain activation [1,2]. In this work we aim at investigating functional connectivity changes in pathological gamblers (PGs) in comparison to healthy controls (HCs) by means of resting state functional Magnetic Resonance Imaging (rs-fMRI). Methods and materials Thirteen HCs and fourteen PGs were recruited (all right handed males; drugs free; mean age 36 ± 10 yrs). All acquisitions were performed through a 1,5 T MRI scanner using a 8-channels phased-array head coil. Multi-session temporal concatenated Independent Component Analysis (concat-ICA) was carried out to achieve activations information on functionally linked brain regions. The resulted components were then matched and compared between groups. Correction for multiple comparisons across space was applied assuming an overall significance of p < 0.05 using permutation testing and threshold-free cluster enhancement. Results Functional connectivity was found to be increased in PGs, compared to HCs, in several networks including: anterior cingulate cortex, accumbens nucleus, head of the caudate nucleus, middle left temporal gyrus, right insula, right cerebellar hemisphere cortex and cerebellar vermis. Conclusion We can conclude that an hyperconnectivity together with an overactivation of specific regions is observed in PGs. The persistent activation of specific functional networks during gambling tasks might represent the neurofunctional basis of PGs state-reduced triggering threshold to gaming underlying the clinical features of gambling disorder. These preliminary results confirms the crucial role of fMRI studies to investigate brain networks and their changes in specific clinical functional disorders. [ABSTRACT FROM AUTHOR]

Chronic administration of L-DOPA to MPTP-treated common marmosets induces marked dyskinesia while repeated administration of equivalent antiparkisonian doses of ropinirole and bromocriptine produces only mild involuntary movements. The occurrence of dyskinesia has been associated with an altered balance between the direct and indirect striatal output pathways. Using in situ hybridisation histochemistry, we now compare the effects of these drug treatments on striatal preproenkephalin-A (PPE-A) and adenosine A2a receptor mRNA expression as markers of the indirect pathway and striatal preprotachykinin (PPT) mRNA and preproenkephalin-B (PPE-B, prodynorphin) mRNA expression as markers of the direct pathway.The equivalent marked losses of specific [3H]mazindol binding in the striatum of all drug treatment groups confirmed the identical nature of the nigral cell loss produced by MPTP treatment. MPTP-induced destruction of the nigro-striatal pathway markedly increased the level of PPE-A mRNA in the caudate nucleus and putamen and decreased the levels of PPT and PPE-B mRNA relative to normal animals. Repeated treatment with L-DOPA for 30 days produced marked dyskinesia but had no effect on the MPTP-induced increase in PPE-A mRNA in the caudate nucleus and putamen. In contrast, L-DOPA treatment normalised the MPTP-induced decrease in the level of PPT and PPE-B mRNA. Repeated treatment with ropinirole produced little or no dyskinesia but markedly reversed the MPTP-induced elevation in PPE-A mRNA in the caudate nucleus and putamen. However, it had no effect on the decrease in PPT or PPE-B mRNA. Similarly, bromocriptine treatment which induced only mild dyskinesia attenuated the MPTP-induced elevation in PPE-A mRNA in the caudate nucleus and putamen with no effect on reduced striatal PPT or PPE-B mRNA. Neither MPTP treatment nor treatment with L-DOPA, bromocriptine or ropinirole had any effect on adenosine A2a receptor mRNA in the striatum.These patterns of alteration in striatal PPE-A and PPT and PPE-B mRNA produced by L-DOPA, bromocriptine and ropinirole show differential involvement of markers of the direct and indirect striatal output pathways related to improvement of locomotor activity and mirror the relative abilities of the drugs to induce dyskinesia. [Copyright &y& Elsevier]

This contribution analyzes the position of biochemical engineering in general and bioprocess engineering particularly in the force fields between fundamental science and applications, and between academia and industry. By using culture technology as an example, it can be shown that bioprocess engineering has moved slowly but steadily from an empirical art concerned with mainly know-how to a science elucidating the know-why of culture behavior. Highly powerful monitoring tools enable biochemical engineers to understand and explain quantitatively the activity of cellular culture on a metabolic basis. Among these monitoring tools are not just semi-online analyses of culture broth by HPLC, GC and FIA, but, increasingly, also noninvasive methods such as midrange IR, Raman and capacitance spectroscopy, as well as online calorimetry. The detailed and quantitative insight into the metabolome and the fluxome that bioprocess engineers are establishing offers an unprecedented opportunity for building bridges between molecular biology and engineering biosciences. Thus, one of the major tasks of biochemical engineering sciences is not developing new know-how for industrial applications, but elucidating the know-why in biochemical engineering by conducting research on the underlying scientific fundamentals. [Copyright &y& Elsevier]

The maximization of biomass productivity in the fed-batch fermentation of Saccharomyces cerevisiae is analyzed. Due to metabolic bottleneck, often attributed to limited oxygen capacity, ethanol is formed when the substrate concentration is above a critical value, which results in a decrease in biomass productivity. Thus, to maximize the production of biomass, the substrate concentration should be kept at the critical value. However, this value is unknown a priori and may change from experiment to experiment. A way to overcome this lack of knowledge is to allow the cells to produce a very small amount of ethanol. This way, the problem of maximizing the production of biomass is converted into that of regulating the concentration of ethanol, for which cell growth can be viewed as a perturbation. A novel adaptive control methodology based on the internal model principle is used to maintain the desired ethanol setpoint and reject the perturbation. Only a single parameter needs to be estimated on-line. Experimental results demonstrate the effectiveness of the proposed control methodology. [Copyright &y& Elsevier]

The effect of a unilateral 6-hydroxydopamine (6-OHDA) lesion and/or repeated administration of levodopa (l-DOPA) to normal and 6-OHDA-lesioned rats on α-synuclein mRNA expression was investigated by in situ hybridization histochemistry. A 6-OHDA lesion of the nigro-striatal pathway alone, confirmed by the loss of nigral tyrosine hydroxylase mRNA expression, markedly decreased α-synuclein mRNA in the lesioned substantia nigra (SN). In contrast, the levels of α-synuclein mRNA in the denervated striatum and nucleus accumbens were not altered. Chronic administration of l-DOPA to normal or 6-OHDA-lesioned rats had no effect on α-synuclein mRNA expression in the SN, striatum or nucleus accumbens. These data confirm that α-synuclein is localized in the nigro-striatal tract but that its gene expression is not regulated by dopamine. [Copyright &y& Elsevier]