Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Cocaine and alcohol are frequently used simultaneously and this combination is associated with enhanced toxicity. We recently showed that active cocaine abusers have a markedly enhanced sensitivity to benzodiazepines. Because both benzodiazepines and alcohol facilitate GABAergic neurotransmission we questioned whether cocaine abusers would also have an enhanced sensitivity to alcohol that could contribute to the toxicity. In this study we compared the effects of alcohol (0.75 g/kg) on regional brain glucose metabolism between cocaine abusers (n = 9) and controls (n = 10) using PET and FDG. Alcohol significantly decreased whole brain metabolism and this effect was greater in controls (26+/-6%) than in abusers (17+/-10%) even though they had equivalent levels of alcohol in plasma. Analysis of the regional measures showed that cocaine abusers had a blunted response to alcohol in limbic regions, cingulate gyrus, medial frontal and orbitofrontal cortices.
Do cocaine abusers show a blunted response to alcohol intoxication in limbic brain regions?

The antibacterial activity of antimicrobial peptides is influenced by various factors such as salt content, pH and the presence of proteins. In this study, we explored the antibacterial action of the human cathelicidin LL-37 in physiologically relevant conditions, i.e. various human wound fluids, human plasma fractions and serum.', 'Radial diffusion assays using Staphylococcus aureus and Escherichia coli were employed for the study of antibacterial effects of LL-37 in the presence of 12 different wound fluids, citrate-, heparin- or EDTA-plasma, or human serum. Glycosaminoglycan content of wound fluids was determined by an Alcian Blue-binding assay. Protein content of wound fluids was measured by the Bradford method. A slot-binding assay was used to study the effects of inhibitors on the interaction between LL-37 and glycosaminoglycans.', 'Five of twelve wound fluids derived from acute wounds showed marked inhibitory effects on the antibacterial action of LL-37. The inhibition was significantly correlated with high glycosaminoglycan content in wound fluid. Analogous to these findings, heparin-plasma strongly inhibited the antibacterial effect of LL-37. The interaction between LL-37 and glycosaminoglycans was abrogated by the cationic polymers DEAE-dextran and chitosan, yielding increased activity of LL-37.
Do glycosaminoglycans inhibit the antibacterial activity of LL-37 in biological fluids?

Induction of delayed hypersensitivity reactions by red tattoos has been occasionally reported. Little is known about the inks used. Azo pigments have been implicated in some instances, but there is only one reported case involving quinacridones.', 'To describe the clinical and pathological features and outcome of skin reactions induced by red tattoo pigments.', 'Six patients with a cutaneous reaction induced by a red tattoo pigment underwent biopsy and prick and patch testing with the inks supplied.', 'We observed seven reactions in the 6 patients. Histology showed various patterns: three lichenoid, two eczematous, and two pseudolymphomatous. Five reactions occurred with azo pigments, and two with quinacridones, in both cases with Violet 19 and Red 122. Four inks were tested. Only one patch test gave a positive result at a late reading (day 7). Prick tests gave negative results. The reactions required various treatments, including laser treatment for 2 patients. Activation of the reaction in 1 case was transient.
Do azo pigments and quinacridones induce delayed hypersensitivity in red tattoos?