In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

Q: Context: Cannabis use disorders (CUD) may influence the course of bipolar disorder (BD), but key confounding factors such as tobacco smoking have not been adequately addressed. This study examined whether CUD was associated with a more severe illness course in tobacco smoking BD patients.', 'A sample of French and Norwegian tobacco smoking patients with BD I and II (N=642) was investigated. DSM-IV diagnoses and other characteristics were obtained through personal interviews using structured questionnaires. The association between CUD and illness course was assessed in regression analyses.', 'In bivariate analyses, CUD was associated with earlier BD onset, higher frequency of manic (in BD I) and depressive episodes and hospitalizations per illness year, and a higher occurrence of psychotic episodes. After controlling for potential confounders, the relationships with earlier BD onset (B=-5.60 95% CI=-7.65 to -3.64), and increased rates of manic episodes (OR=1.93, 95% CI: 1.15 to 3.23) and hospitalizations (OR=2.93, 95% CI: 1.85 to 4.64) remained statistically significant.\Question: Is cannabis use disorder associated with greater illness severity in tobacco smoking patients with bipolar disorder?

A: Despite the multivariate approach, differences between the two samples may lead to spurious findings related to hidden confounders. Substance use and mood episode information was collected retrospectively, and potential birth cohort effects could not be controlled for.
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Q: Context: Opioid-induced spastic paraplegia after transient spinal cord ischemia during aortic surgery has been reported. Opioids modulate neurotransmission through mu () opioid receptors (MORs) in the spinal ventral horn. However, their effects during ischemic insult are not understood.', 'The effects of the selective agonist [D-Ala(2),-N-Me-Phe(4), Gly(5)-ol]enkephalin (DAMGO) on ischemia-induced agonal currents were examined in the spinal lamina IX neurons of neonatal rats by using the whole-cell patch-clamp technique. Ischemia was simulated in vitro by oxygen/glucose deprivation.', 'DAMGO (1 M) produced outward currents in ~60% of spinal lamina IX neurons at a holding potential of -70 mV. Superfusion with ischemia-simulating medium elicited an agonal current. The latency was 457 18 s. Despite its neuromodulatory effects, DAMGO did not significantly change the latencies of the agonal currents with (440 23 s) or without (454 33 s) DAMGO-induced currents.\Question: Does the mu opioid receptor activation affect ischemia-induced agonal currents in rat spinal ventral horn?

A: Activation of MORs does not influence ongoing ischemia-induced neuronal death. Our findings indicate that MOR agonist administration should be suitable as an anesthetic during aortic surgery.
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Q: Context: Chronic venous insufficiency (CVI) results when the veins in the legs no longer pump blood back to the heart effectively. Microparticles (MPs) are small membrane vesicles released by several circulating and vascular cells upon activation or apoptosis.', 'The purpose of this study was to assess the subpopulations of circulating endothelial (EMPs) and platelet microparticles (PMPs) in CVI, and to disclose their contribution in mediating dysfunction of human peripheral venules.', 'Human peripheral venules were explanted during leg surgery on patients with CVI and on control subjects (C); concurrently, blood samples were collected and circulating MPs isolated. The techniques used were: flow cytometry, fluorescence and electron microscopy, myograph technique and western-blotting technique.', 'The results showed that compared with controls, patients with CVI had: (i) a marked elevation of circulating EMPs and PMPs; (ii) a structural modification of the venous wall consisting of activation of endothelial and smooth muscle cells, an abundance of intermediary filaments and synthesis of hyperplasic-multilayered basal lamina; (iii) a significantly altered reactivity of the venous wall, closely associated with EMPs and PMPs adherence; (iv) altered contractile response to noradrenaline, acetylcholine, 5-hydroxytryptamine and KCl, and an impeded relaxation in response to sodium nitroprusside; and (iv) a substantially increased protein expression of tissue factor (TF) and of P-Selectin both in the venular vascular wall and on the surface of EMPs and PMPs.\Question: Is chronic venous insufficiency associated with elevated level of circulating microparticles?

A:
The findings indicate that CVI is accompanied by an enhanced release of EMPs and PMPs that contribute to altered dysfunctional response of the venous wall.
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