instruction:
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.
question:
Context: Intrathecal adenosine is antinociceptive under conditions of central sensitization, but not in response to acute stimuli in normals. The reasons for this selective circumstance of action remain unclear, but some evidence links adenosine's antinociceptive effects to release of norepinephrine by terminals in the spinal cord. The purpose of this study was to test whether spinal adenosine induces norepinephrine release selectively in settings of hypersensitivity.", 'Rats randomly assigned to spinal nerve ligation, sham operation, or no operation were anesthetized. A microdialysis fiber was implanted in the spinal cord dorsal horn at the L5-L6 level and perfused with artificial cerebrospinal fluid. After washout and a baseline sample period, adenosine at various concentrations was infused through the fiber for 150 min, and samples were collected every 15 min.', "In ligated, but not in sham or normal animals, adenosine perfusion increased norepinephrine in spinal cord microdialysates in a concentration-dependent manner. The effects of adenosine plateaued after 75 min and remained stable until the end of the experiment. Intravenous injection of selective adenosine A1 and A2 receptor antagonists revealed that adenosine's effect on spinal norepinephrine release was A1 receptor mediated.\Question: Does intraspinal adenosine induce spinal cord norepinephrine release in spinal nerve-ligated rats but not in normal or sham controls?
answer:
This is the first study to provide direct evidence that adenosine is able to release norepinephrine in spinal cord dorsal horns in living animals. However, this effect was only seen in animals after spinal nerve ligation. These data are consistent with behavioral studies demonstrating that adenosine's antinociceptive effects in rats after spinal nerve ligation is totally dependent on intact spinal noradrenergic terminals and can be blocked by spinal alpha 2-adrenergic receptor antagonists.


question:
Context: Insomnia increases in prevalence with age, is strongly associated with depression, and has been identified as a risk factor for suicide in several studies. The aim of this study was to determine whether insomnia severity varies between those who have attempted suicide (n = 72), those who only contemplate suicide (n = 28), and those who are depressed but have no suicidal ideation or attempt history (n = 35).', 'Participants were middle-aged and older adults (age 44-87, M = 66 years) with depression. Insomnia severity was measured as the sum of the early, middle, and late insomnia items from the Hamilton Rating Scale for Depression. General linear models examined relations between group status as the independent variable and insomnia severity as the dependent variable.', 'The suicide attempt group suffered from more severe insomnia than the suicidal ideation and non-suicidal depressed groups (p < 0.05). Differences remained after adjusting for potential confounders including demographics, cognitive ability, alcohol dependence in the past month, severity of depressed mood, anxiety, and physical health burden. Moreover, greater insomnia severity in the suicide attempt group could not be explained by interpersonal difficulties, executive functioning, benzodiazepine use, or by the presence of post-traumatic stress disorder.\Question: Is insomnia associated with suicide attempt in middle-aged and older adults with depression?
answer:
Our results suggest that insomnia may be more strongly associated with suicidal behavior than with the presence of suicidal thoughts alone. Accordingly, insomnia is a potential treatment target for reducing suicide risk in middle-aged and older adults.


question:
Context: We developed a lactoferrin conjugate by modifying bovine lactoferrin (bLF) with a 40-kDa branched poly(ethylene glycol) (PEG) molecule (designated 40 k-PEG-bLf), and we evaluated its in vitro activities and pharmacokinetic properties.', 'We prepared 40k-PEG-bLf by amino conjugation with N-hydroxysuccinimide-activated PEG. This conjugate was purified by cation exchange chromatography and its in vitro biological activities, such as iron binding, anti-inflammatory effects, and resistance to proteolytic enzymes were investigated. In vivo pharmacokinetics analyses, were also performed to examine the rate of clearance from the plasma in rats.', 'The 40k-PEG-bLf conjugate was fully active in iron binding and exhibited 97.1 +/- 5.5% (mean +/- S.E., n = 6) of the original anti-inflammatory activity. The in vitro peptic susceptibility of 40 k-PEG-bLf revealed that the proteolytic half-life increased at least 6-fold that of unmodified LF. This PEGylated conjugate demonstrated a plasma half-life that was 8.7-fold longer than that of the unmodified bLF in rats.\Question: Does lactoferrin conjugated with 40-kDa branched poly ( ethylene glycol ) have an improved circulating half-life?
answer:

The 40k-PEG-bLf exhibited improved in vitro bioactivity and stability and enhanced pharmacokinetic properties as compared to those of the unmodified bLF and the 20 k-PEG-bLf conjugate, which was recently developed by PEGylation of bLF with a 20-kDa branched PEG [Nojima Y. et al. Bioconjugate Chem. 19:2253-2259 (2008)].