instruction:
Given a passage with a context and an answer, 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.
question:
Context: The aim of the present study was to determine the potential therapeutic value of the lazaroid U-83836E on blood brain barrier (BBB) breakdown and edema with respect to the changes in the synaptosomal Na+/K+ and Mg(2+)/Ca(2+)-adenosinetriphosphatase (ATPase) activities, tissue malondialdehyde levels and the neuronal viability in the rat brain subjected to cerebral trauma.', 'Traumatic brain injury (TBI) was introduced by applying a 75 gm. cm force to the right parietal cortex using the weight-drop method. The first set of animals was used for determining time course changes of the synaptosomal Na+/K+ and Mg(2+)/Ca(2+)-ATPase and the malondialdehyde levels and were sacrificed 2, 6 and 24h after lesion production. A group of the animals was treated with U-83836E proir to TBI and sacrificed 24h after cerebral injury. A second set of animals was used for evaluating the alterations in BBB disruption and tissue water content and were sacrificed 2, 6 and 24h after lesion production. Two groups of animals were treated with U-83836E and sacrificed after 2 and 24h following TBI. U-83836E was given intraperitoneally thirty minutes before trauma at a dose of 10 mg/kg. Neuronal necrosis was also evaluated in the groups of U-83836E and physiological saline-treated animals.', 'Extravasation of Evans blue into the traumatized hemisphere was maximum at 2h (p<0.001) and returned close to the control levels at 24h after TBI (p>0.05). Edema had developed progressively over time and reached the maximum degree of 2.1% (p<0.001) at 24h. U-83836E showed no effect on the BBB breakdown and the tissue water content at 2h and still had no effect on the BBB breakdown after 24h following the trauma (p>0.05), although it reduced edema after 24h (p<0.01). The losses of Na+/K+ and Mg(2+)/Ca(2+)-ATPase activities were found as 39.5% (p<0.001) and 29.4% (p<0.01) of the control value, respectively, and remained at the decreased levels throughout the experiment. Malondialdehyde level continued to increase over time reaching up to 209% (p<0.001) of the control value 24h after TBI. Both ATPase activities were improved to near control values (p>.05) by the effect of U-83836E. U-83836E inhibited the increase of lipid peroxidation (p<0.001) and also salvaged neuronal necrosis (p<0.05).
Answer: U-83836E given prophylactically after cerebral trauma appears to reduce edema, possibly by inhibiting increases in lipid peroxidation and by stabilizing ATPase. Further studies are recommended to verify the similar effects of the brain penetrating lazaroids when they are given after trauma.
answer:
Does lazaroid attenuate edema by stabilizing ATPase in the traumatized rat brain?


question:
Context: Side effects of mitotane (o,p'-DDD) have suggested estrogenic effects.", "The objective of the study was to explore o,p'-DDD potential estrogenic effect on SHBG and corticosteroid-binding globulin (CBG).", 'Human hepatoma cell lines (HepG2), lacking estrogen receptor (ER)-alpha, and Hep89, stably transfected by ERalpha, were used.', 'The study was conducted at an academic research laboratory and medical center.', 'The study included 10 male patients with recurrent adrenal carcinoma, receiving mitotane (4-6.5 g daily) for more than 6 months.', 'The main outcome measures were SHBG/CBG mRNA levels measured by real-time PCR, culture medium SHBG/CBG concentrations measured by specific immunoassays, and transient transfection experiments with human SHBG proximal promoter reporter constructs.', "Increased serum SHBG and CBG concentrations, which exceeded normal male limits, were observed in most mitotane-treated patients. In the HepG2 cell line, 17beta-estradiol (E2) or o,p'-DDD treatment had no effect on mRNA or SHBG/CBG concentrations. In contrast, in the Hep89 cell line, E2 increased concentrations of SHBG (r = 0.44, P < 0.0001) and CBG (r = 0.585, P < 0.0001) secreted into culture media in a dose-dependent manner. o,p'-DDD significantly increased SHBG (150% vs. control, P < 0.05) and CBG (184% vs. control, P < 0.05) production by Hep89 cells, at a concentration of 2 x 10(-5) m. Transient transfection experiments in Hep89 cells showed that E2 or o,p'-DDD treatment did not increase the transcriptional activity of the minimal proximal promoter of human SHBG gene.
Answer: Mitotane increased SHBG/CBG gene expression and liver production by mechanisms requiring the presence of ERalpha.
answer:
Does mitotane have an estrogenic effect on sex hormone-binding globulin and corticosteroid-binding globulin in humans?


question:
Context: Nonviral vectors based on polyethylenimine (PEI) usually contain an excess of PEI that is not complexed to DNA. Since unbound PEI contributes to cellular and systemic toxicity, purification of polyplexes from unbound PEI is desirable.', 'Size exclusion chromatography (SEC) was used to purify PEI polyplexes of free PEI. Transfection properties of purified polyplexes and the effect of free PEI on gene delivery were studied in vitro and in vivo after systemic application into mice.', 'SEC did not change the size and zeta-potential of polyplexes. Independent of the amount of PEI used for complex formation, purified PEI polyplexes had the same final PEI nitrogen/DNA phosphate ratio of 2.5. Notably, purified PEI polyplexes demonstrated low cellular and systemic toxicity. High transfection efficiency was achieved with purified polyplexes at high DNA concentrations (8-15 microg/ml). At low DNA concentrations (2-4 microg/ml) gene transfer with purified particles was less efficient than with polyplexes containing free PEI both in vitro and in vivo. Mechanistic studies showed that free PEI partly blocked cellular association of DNA complexes but was essential for the following intracellular gene delivery. Adding free PEI to cells treated with purified particles with a delay of up to 4 h resulted in significantly enhanced transfection efficiency compared with non-purified particles or purified particles without free PEI.
Answer: This study presents an efficient method to remove free PEI from PEI polyplexes by SEC. Our results from transfection experiments demonstrate that free PEI substantially contributes to efficient gene expression but also mediates toxic effects in a dose-dependent manner. Purified polyplexes without free PEI have to be applied at increased concentrations to achieve high transfection levels, but exhibit a greatly improved toxicity profile.
answer:

Does purification of polyethylenimine polyplexes highlight the role of free polycations in gene transfer?